JPS62239132A - Camera - Google Patents

Abstract

PURPOSE:To thin a camera and to reduce the power consumption of a film feeding motor by using a passage between an inside rail surface of a film and a retaining plate fixed to the camera as a film passage. CONSTITUTION:When a rear cover 4 is closed with the leader part of a film F let outside, the film whose existence is detected by a switch 21 is wound into a cartridge P and is fed in the passage between a retaining plate 3 and an inside rail surface 1e with rolls 8 and 6 by the start of blind exposure. At such a time, the film is pressed to the retaining plate by a sprocket 14 charged counterclockwise around a shaft 17 by a spring. Consequently, a pressure plate spring is made unnecessary, and the planeness of the film is improved, and the camera is made thin by the thickness of the pressure plate spring, and the friction between the pretension of a contact and the film is reduced to reduce the load of the motor because the switch 21 which is made conductive to a metallic plate 9 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a camera, and more particularly to a camera that can easily load film and is of an automatic film feeding type.

[Background of the invention]

In conventional cameras, film loading is quite troublesome, and in order to improve this problem, various proposals have recently been made for cameras that allow film loading to be performed more easily than in conventional cameras.

The present applicant has already made some proposals regarding a simple loading type camera that allows film loading to be performed much more easily than conventional cameras, and according to this proposal, film loading can be performed extremely easily. Not only that, but it has also been shown that it is possible to create a camera that is more waterproof than conventional cameras.

FIG. 5 is a sectional view of the camera proposed by the applicant. In the same figure, 27 is the camera body, 27m is the a4') Rohne chamber formed in the main body 27, and 27b
is the spool chamber. 28 is a small back cover provided on the back side of the main body 27 and can open only the cutrone chamber 27m; 29 is a front cover of the camera; 30 is a back cover 28
31 is a film winding spool housed in the spool chamber 27b; 32 is a film feeding motor housed in the spool 31; 33 is a front cover 29; A protective glass is attached to the front opening, 34 is a lens barrel carrying a photographing lens 35, 36 is an aperture glass plate that closes the aperture hole of the camera body 27, and 37 is an ano-9-a glass plate for holding the film. A pressure plate 36 is brought into pressure contact with the pressure plate 36, a pressure plate spring 38 is attached to the rear cover 30 and biases the pressure plate 37 toward the front of the camera, and 39 is a cutrone P.
An unwinding roller 40 is pivotally attached to the inside of the back cover 28 by a single pin 41 and is attached by a spring 42 to the inside of the camera to pull out the film from inside the Yatrone P by engaging the film leader portion exposed from the inside. A lever 43 is disposed opposite to the surface of the unwinding roller 39 and is rotatably supported by the lever 40. A lever 44 is a first back cover roller that is biased toward the inside of the back cover 28. a second back cover roller rotatably supported on the back cover; 45, a film leader entrance opening formed between the back cover opening edge of the rear cover 30 and the engaging surface 28& of the back cover 28; 46, a film leader section inlet; A film leader detection switch 47 for detecting the presence of the film leader Fa in the leader entrance 45 engages with a perforation hole of the film pulled out from the cartridge P and moving parallel to the aperture glass plate 36. It's a tin rocket.

In a camera having the structure described above, when loading film, the back cover 28 is opened and the cartridge P is placed in the armpit chamber 2.
7&, when the back cover 28 is closed while leaving the film leader section Fm outside the camera, the film leader section F& is detected by the film leader section detection switch 46, so that the above-mentioned film winding and rewinding are performed. The motor 32 rotates in reverse, and the film leader Fa is drawn into the camera. When the tip of the film leader part Fm enters the camera up to the position of the first back cover row 243, the motor is switched to the normal rotation direction and the film leader part Fa moves between the front glass plate 36 and the pressure plate 37. The film advances between the pressure plate 37 and the aperture glass plate 36 while being pressed against the aperture glass plate 36 by the pressure plate 37, and when it is wound around the spool 31, the motor will be stopped. In addition, the film leader part Fa is connected to the pressure plate 37 and the a/4'-cha glass plate 36.
t! of the film during the entire film passage between t! -ft
When the teeth of the tin rocket 47 are inserted into the rotation holes, the sprocket 47 is rotated as the film moves, and a detector that detects the rotation of the sprocket 47 detects the amount of film feeding.

The camera proposed by the applicant with the above structure has the advantages of being extremely easy to load film and having a small back cover, making it durable and waterproof. There were problems like.

(1) In the above camera, the film is pressed against the aperture glass plate 36 by the pressure plate 37 in the aperture area, as in conventionally known cameras, but it is difficult to keep the spring pressure of the pressure plate spring 38 constant. The film cannot be evenly adhered to the entire surface of the 4-cha glass plate 36, and therefore the film surface is not as flat as the a-matrix glass surface.

(11) Since the thickness of the camera must be increased by the provision of the pressure plate spring 38, the camera becomes larger.

(iiD In the above camera, as shown in FIG. 6, the film leader detection switch 46 has two switch pieces 4.
6m and 46b, when the film leader part Fa presses the switch piece 46m, the switch pieces 46m and 46b separate, and when the film leader part Fa is not in the film leader part entrance port 45, the switch pieces 46a and 46b come into contact. However, in the case of a thin film, the amount by which the film leader section displaces the switch piece 46m in the direction away from the switch piece 46b becomes small, making detection almost impossible.

Therefore, in order to detect even a thin film with sufficiently high sensitivity, it is necessary to apply strong pretension to the switch piece 46a in the film direction.
When the switch piece 46a presses the film leader part Fm with a strong force, the frictional force between the film leader part Fm and the surface that comes into contact with it becomes large, and therefore the power consumption of the motor decreases when the film leader part is rewinded. becomes larger.

[Purpose of the invention]

The purpose of this invention is to solve the problems of the camera shown in FIGS. 5 and 6, which is the first invention of the present applicant, to reduce the thickness of the camera, and to provide a film feeding part. The purpose of the present invention is to provide an improved camera that consumes less power.

[Summary of the invention]

In the improved camera according to the present invention, the pressure plate and pressure plate spring provided in conventional cameras are abolished, and a film pressing plate is fixed to the film outer rail surface, and there is a space between the film pressing plate and the film inner rail surface. The film is characterized by having a film passage. Therefore, since the camera of the present invention does not have a pressure plate or a pressure plate spring, the thickness of the camera can be reduced, and as a result, the camera can be made smaller.

Further, in the camera of the present invention, when the film leader section is present in the film leader section entrance path, at least one switch piece that contacts one surface of the film leader section and the film leader section in the film leader section entrance path are provided. A conductive piece may be provided which contacts the other side of the film leader when the film leader exists, but which contacts the switch piece when the film leader does not exist. It is possible to detect thin film, which was difficult to detect with conventional cameras, and since the switch piece and the conductive piece are placed opposite to each other on both sides of the film leader, it is possible to detect thin film even when handling thin film. There is no need to press the switch piece against the film leader section with a particularly strong force, and therefore, the frictional force against the film leader section does not increase, so there is no fear that the power consumption of the film feeding motor will increase.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

FIG. 1 is a schematic vertical sectional view of the camera of the present invention, FIG. 2 is a horizontal sectional view, and FIGS. 3 and 4 are partial perspective views.

In FIGS. 1 and 2, 1 is a camera body, 2 is a photographing lens, and 3 is a film holding plate. The film holding plate 3 is fixed to the camera body 1 as described later.

1 & is A? -cha, lb is a spool chamber, and in the spool chamber 1b is provided a spool 12 that is rotatable around a shaft 13 driven by a motor (not shown). 1° is a fork, and the fork 1o is rotatable around a shaft 11, and when the fork 10 rotates counterclockwise in the figure, the film F is wound into the cartridge P. Reference numeral 4 denotes a back cover which can be rotated around a shaft 5 to open and close only the cartridge storage chamber 1c, and a metal plate 9 is fixed to the inside of the back cover 4. The metal plate 9 has a spring property at one end, and includes a roller holding portion 9a that rotatably holds the back cover feeding roller 8 pressed against the feeding roller 6 at its tip, and a detection switch 21 to be described later.
and a conductive piece portion 9b disposed opposite to the conductive piece portion 9b.

The feed roller 6 is rotatable around a shaft 7 fixed to the camera body 1, is connected to a drive gear train (not shown), and is driven by a motor (not shown).

A film entrance path 4a is provided between the back cover 4 and the opening edge of the rear cover 26, and a light shielding material 20 such as Moltoprene is pasted on the inside of the back cover 4. When the film F is drawn into the camera, the light shielding material 20 blocks the film entrance path 4a by its elastic force, and serves to prevent light from leaking into the camera.

In the camera of the present invention, there is no pressure plate and pressure plate spring provided in conventional cameras, and the film F is formed by the difference in level between the so-called inner rail surface 1e and outer rail surface 1d of the camera body 1, as shown in FIG. It is arranged in the space created by the film and is regulated by the film holding plate 3. That is, in the camera of the present invention, a flat film holding plate 3 is fixed to the outer rail surface 1d by a plurality of screws B, and a film path is formed between the film holding plate 3 and the film inner rail surface 1e. Film F is arranged at . The screw insertion hole 3a penetrated through the film holding plate 3 is a blank hole and has a diameter larger than the diameter of the screw B, so by loosening the screw B, the fixed position of the film holding plate 3 can be adjusted. can be adjusted.

FIG. 3 is a perspective view of a film IJ-da part detection mechanism in the camera of the present invention.

As shown in FIGS. 2 and 3, the metal plate 9 fixed to the back cover 4 includes the aforementioned roller holding portion 9 and a conductive piece portion 9b that can come into contact with a switch piece of a detection switch 21, which will be described later. have. The detection switch 21 arranged near the film entrance path 4a has a first contact piece 21 & a second contact piece 21b%.
The first contact piece 21m is always in contact with the conductive piece portion 9b of the metal plate 9 when the back cover 4 is closed. Further, the second contact piece 21b of the detection switch 21 is provided at the position of the perforation w/hole 25 of the film F, and when the film F is moved and inserted into the perforation hole 25, the metal plate 9 conducts electricity. It contacts the piece 9b. Further, the third contact piece 21c is the second contact piece 21c.
Above b? - It is provided at a position away from the foration hole 25 so that it comes into contact with the conductive piece portion 9b when the film F is not in the film entrance path 4.

Therefore, the detection switch 21 has a first contact piece 21m and a second contact piece 2.
1b detects the mother fusion hole 25t;
The first contact piece 21& and the third contact piece 21a are configured to detect the presence or absence of the film F, and the detection switch 21 is connected to a circuit (not shown) on the camera body side. By arranging the metal plate 9 having the conductive piece 9b on the back cover 4 side in this way, it can be connected to the circuit on the camera body side and the conductive piece 9b on the back cover 4 side which can be opened and closed using a gold flexible plate, a lead wire, etc. This has the advantage that it is extremely easy to implement the circuit, since it is no longer necessary to do so, and all the mounting is done only on the camera body side.

FIG. 4 shows a detection section for detecting the amount of film feed, and the structure of the detection section will be explained with reference to FIGS. 2 and 4.

Reference numeral 14 denotes a sprocket for detecting the film feed amount. A sprocket first gear 15 is formed integrally with the sprocket 14. The sprocket rocket 14 and the sprocket first gear 15 are connected to a connecting plate 19. It is rotatably supported around a shaft 18 fixed to. 16 is a sprocket second gear, and the tin rocket second gear 1
6 is rotatably supported around a shaft 17 fixed to the camera body 1, and is constantly engaged with the Sugerocket first gear 15. On the other hand, the connecting plate 19 is also rotatable about the shaft 17, and is biased counterclockwise by a spring 22. The number of teeth of the sprocket first gear 15 and the sprocket second gear 16 are set to be the same, and the sprocket 14 has eight sprocket teeth that mesh with the no-kuforation holes 25 of the film. Therefore, when one frame of the film screen is fed, sprocket 1
4 makes exactly one revolution. The counter contact piece 23a detects this rotation of the sprocket 1401.

23b and every time it contacts the eight conductive /4' turns 24 printed on the sprocket second gear 16 /J? It is now possible to generate ruses.

Next, the operation and operation method of the camera constructed as described above and according to the nine embodiments will be explained.

First, when the cartridge P is loaded into the cartridge storage chamber IC and the back cover 4 is closed with part of the leader of the film F being exposed outside the camera, the back cover opening/closing detection switch (not shown) is turned on.
At the same time, the state between the first contact piece 21 and the third contact piece 21c, which detects the presence of the film F in the film entrance path 4a, becomes OFF', and this signal causes the motor (
(not shown) is energized, thereby driving the fork 10 counterclockwise to start empty rewinding in which the film F is wound into the cartridge P. When the film F is unwound and runs, the second contact piece 21b that detects the conductive hole 25 contacts the conductive piece part 9b of the metal plate 9, and then returns to non-contact. The ON and OFF states are repeated between the second contact piece 21b and the second contact piece 21b. This ON,
A pulse is generated every time the OFF operation is performed, and the number of pulses is counted to detect the amount of unrolled coal.

When the end of a part of the leader of the film F passes the tip of the third contact piece 21c, the third contact piece 21a touches the conductive piece part 9b of the metal plate 9.
At this time, the connection between the first contact piece 21a and the third contact piece 21e becomes ON, and after this signal turns off the current to the motor, reverse current to the motor starts immediately, and the feeding starts. The film F is sent out between the roller 6 and the back cover feeding roller 8, and empty winding (so-called empty feeding) is started. When the film leader comes into contact with the sprocket 14 due to empty winding, the sprocket rocket 14 is moved by the spring 2.
Sprocket second gear 1 about axis 17 against
It revolves around 6 and moves away from the film surface. When the film is fed to the position where the teeth of the sprocket 14 engage with the hole 25 of the film F, the teeth of the sprocket 14 (7) are machined into the hole 25 of the film F. During feeding, they are always engaged and rotated as the film moves, and a pulse is generated every time the conductive knot turns 24 on the second sprocket gear 16 are detected, thereby detecting the amount of film movement. When it is detected that dry winding has been performed for an amount equal to or greater than the above-mentioned dry coal amount, the motor energization is stopped and dry winding is completed. The subsequent winding of one frame of film for each photographing and auto-return after all frames have been photographed are performed using known techniques, and therefore will not be described here.

In the above embodiment, a sprocket is used as a means for detecting the amount of film feeding, but the method is not limited to this, and a photoelectric detection method using a photocoupler or the like may be used.

However, in this case, a means is required to prevent light from leaking into the screen.

Further, when the back cover of the camera is closed without loading film, the empty winding operation may be started without performing the empty rewinding operation. However, in this case, by providing a timer circuit, the motor will be turned off after a predetermined time.
It is better to make it so that it will be F. In addition, the first contact piece 21
When the foration signal detected by m and the second contact piece 21b is not output, the idle rewinding or idle winding operation may not be performed. Furthermore, the third contact piece 21
e is abolished and only the first contact piece 211 and the second contact piece 21b are used, and when the above-mentioned distortion signal is not generated within a certain period of time, the idle rewinding is stopped and the idle winding operation is started. You can also create a sequence like this.

〔Effect of the invention〕

As explained above, the camera of the present invention is configured so that the film pressure plate is fixedly attached to the camera body, so the pressure plate spring that was conventionally required is not required, and the structure is simplified. Eliminates the drawback of poor film flatness due to variations in pressure plate spring pressure.
Furthermore, it is possible to reduce the size of the camera by the space of the pressure plate spring, resulting in the effect that the camera can be configured compactly.

In addition, in the camera of the present invention, the switch for detecting the film leader during empty rewinding is configured to conduct electricity between the contact pieces provided on the camera body side through a metal plate provided on the back cover side. Therefore, the britension of the contact piece can be reduced, and therefore the friction between the contact piece and the film is reduced, and the effect of reducing the motor load when the film is idly rewinded can be obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical sectional view of an embodiment of the camera according to the present invention, FIG. 2 is a horizontal sectional view of the camera of FIG. 1, FIG. 3 is an enlarged perspective view of a part of FIG. 2, and FIG. 2 is an enlarged perspective view of the portion shown in FIG. 2, FIG. 5 is a horizontal sectional view of the camera which is the first invention of the present applicant, and FIG. 6 is an enlarged perspective view of a portion of FIG. 5. It is. 1...Camera body, 2...Photographing lens, 3.
...Film holding plate, 4...Back cover, 4a...Film entrance path,
6... Feeding roller, 8... Back cover feeding roller, 9
... Metal plate, 9b... Conductive piece part, 10...
・Fork, 12... Spool, 14... Sprocket, 15... Sprocket 1st gear, 16... Sprocket 2nd gear, 19... Connecting plate, 2o... Light shielding material, 21...
...Detection switch, 22...Spring, 23a, 2
3 b = Force') 7) Contact piece, 24... Conductor/mother turn. ! -! [Honda Kodaira] Shouting 1--" Figure 1 Figure 6

Claims (1)

[Claims] A camera that has a back cover that allows only the cartridge storage chamber to be opened and closed, and that film is automatically fed by closing the back cover while leaving the film leader section outside the camera. A film holding plate arranged at a constant distance from the film inner rail surface of the camera body is fixed to the camera body, and a film passage is formed between the inner rail surface and the film holding plate. A camera featuring