JPH09244132A - Film pressure plate for camera provided with magnetic recording part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute magnetic recording and reproducing with high reliability by reducing dust and damage to a film caused by the wearing of the peripheral part of a film pressure plate, while securing the flatness of the film, and further, a failure in the contact of a magnetic head with the film caused by the dust due to the wearing. SOLUTION: A large number of small protrusions 8 whose vertex parts are formed to be on the same plane are formed in the pressure plate central part on a film surface of the film pressure plate 2 having the magnetic head 12 attached to the side of the film surface. In the peripheral part outside a picture frame size of the film pressure plate 2, plural projections 10 which are discontinuous in the width direction of the film and on the same plane as the vertex parts of the small protrusions 8 and have contact areas larger than ones of the small protrusions 8 are formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film pressure plate of a camera equipped with a magnetic head capable of recording and reproducing various kinds of magnetic information on a film having a magnetic information recording section.

[0002]

2. Description of the Related Art In recent years, a camera having a function of recording or reproducing various kinds of information in a magnetic information recording portion using a film having a magnetic information recording portion has been disclosed in US Pat. Proposed. In this type of camera, in order to record or reproduce various information in the magnetic information recording section, it is necessary to dispose the magnetic head on the film pressure plate side, which is the magnetic layer side of the film, and the magnetic head may be attached to the pressure plate. For example, it is well known from Japanese Patent Laid-Open No. 3-264934.

Further, in a conventional camera, in order to prevent the film and the film pressure plate from sticking to each other and from scratching the film due to dust or the like, a large number of fine spherical projections are formed on the film contact surface of the film pressure plate. The film pressure plate having the above-mentioned structure is known from, for example, Japanese Utility Model Laid-Open No. 163939/1983. Further, a film pressure plate in which the arrangement interval of the spherical projections is made wider in the pressure plate central portion than in the pressure plate peripheral portion to reduce scratches on the film due to abrasion in the pressure plate central portion is disclosed in Japanese Utility Model Publication No. 4-85430. Proposed.

[0004]

In the case of a conventional type of film, that is, a type of film in which the film is not completely contained in the cartridge and which has to be manually loaded, the photographer needs to manually handle the film. Then, the film tip was pulled out from the cartridge to the vicinity of the take-up spool of the camera and set on the take-up spool so that the film cartridge was loaded in the camera. For this reason, in the above-mentioned conventional film, it is sufficient to consider only the scratches of the film caused by the abrasion of the film thickness direction surface and the film pressure plate.

However, in a film cartridge which has a magnetic information recording section in which the film is completely housed in the cartridge and is capable of being automatically loaded, when the film front end is sent out from the cartridge, the film front end The film side of the pressure plate,
In particular, the film runs so as to wear the peripheral portion on the cartridge side. In addition, abrasion is likely to occur around the spool of the film pressure plate where the frictional force increases due to the bending of the film.

Therefore, if spherical projections having a small contact area are provided in the peripheral portion of the film pressure plate, or if the spacing between the spherical projections is widened, a large force is applied to the contacting portions, and the tips of the projections are scraped by the film. It becomes easy to generate dust and scratches the film. Further, dust may be attached to the gap surface of the magnetic head to cause data reading error and data writing error.

Therefore, the present invention has been made to solve the above-mentioned problems, and while securing the flatness of the film, it reduces dust and scratches on the film caused by the abrasion of the peripheral portion of the film pressure plate, and also causes the abrasion. An object of the present invention is to provide a film pressure plate for a camera with a magnetic information recording unit, which can perform reliable magnetic recording and reproduction by reducing contact failure between a magnetic head and a film, which is caused by dust.

[0008]

In order to achieve the above object, a film pressure plate of a camera with a magnetic information recording unit of the present invention uses a film having a magnetic track, and photographing information can be magnetically recorded on the magnetic track. A film pressure plate for a camera, which is arranged at a predetermined position on the film contact surface side and performs magnetic recording on the film, and a large number of first magnetic heads arranged in the film contact surface and sharing the top envelope surface. 1 projection, which is outside the photographing screen area, is arranged in the film width direction around the film feeding direction end in the film contact surface, shares the top envelope surface with the first projection, and has a contact area with the film. Is provided with a plurality of second protrusions each having a larger contact area with the film than the first protrusion.

Further, the film pressure plate of the camera with the magnetic information recording section of the present invention is characterized in that the second protrusion has a shape in which the first protrusion is extended in the film feeding direction.

Further, the film pressure plate of the camera with the magnetic information recording unit of the present invention is characterized in that the first projections are uniformly arranged in a grid pattern at a predetermined pitch on the film contact surface side. To do.

That is, in the film pressure plate of the camera with the magnetic information recording portion of the present invention, a large number of first projections sharing the top envelope surface are arranged in the film contact surface, and the first projection and the top envelope are also arranged. A plurality of second projections that share the surface and have a contact area with the film larger than that of the first projection are formed outside the photographing screen area and around the end of the film in the film feeding direction in the film contact surface. Arranged in the direction. Magnetic recording is performed on the film by a magnetic head arranged at a predetermined position on the film contact surface side.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the structure of a film pressure plate of a camera with a magnetic recording unit according to an embodiment of the present invention, and FIG. 2 is a front view of the film pressure plate seen from the film surface side. FIG. 3 is a cross-sectional view for explaining a use state when a camera to which this film pressure plate is applied is cut in a vertical direction, and FIG. 4 is a cross-sectional view for explaining a use state when the camera is cut in a horizontal direction. FIG.

The film pressure plate 2 is fixed to the camera body 6 with screw holes 2b so that the position regulating surface 2a in the thickness direction of the film 4 is brought into contact with the camera body 6, and the position of the film 4 in the optical axis direction is fixed. regulate. On the surface of the film pressure plate 2 on the film surface side, that is, on the film pressure plate surface 2c, in the range corresponding to the screen size of the central portion of the film pressure plate,
A large number of small projections 8 whose tops are formed on the same plane are formed. The small projections 8 are uniformly arranged in a lattice pattern on the film pressure plate surface 2c at a predetermined pitch.

The left and right peripheral portions of the film pressure plate 2 outside the screen size are discontinuous in the film width direction and have a top on the same plane as the top of the small protrusions 8 and contact with the film 4. A plurality of large protrusions 10 having an area larger than that of the small protrusions 8
Are formed.

FIG. 5 is a view showing the shape of the large protrusions 10, the cross section AA showing the cross sectional shape in the film width direction, and the cross section BB showing the cross sectional shape in the film running direction. In order to prevent such a problem that the film 4 is caught on the large protrusion 10 and becomes immobile, a slope 10b or a curved surface is formed between the smooth surface 10a at the top of the large protrusion 10 and the film pressure plate surface 2c as shown in FIG. To be done.
Further, the smooth surface 10a of the large protrusion 10 and the boundary portion between the film pressure plate surface 2c and the inclined surface 10b (or curved surface) are rounded so as not to become an edge. As a material for the film pressure plate 2, a plastic material, a metal material, or the like is used.

A magnetic head 12 is attached to the film surface side of the film pressure plate 2, and as shown in FIGS.
An elastic member 16 to which a pad 14 is attached is attached to the camera body 6 with a screw 18 in order to ensure contact between the magnetic head 12 and the film 4. Further, this camera comprises an exterior member 20, a film cartridge 22, and a spool 24 for winding the film 4. The small protrusions 8 and the large protrusions 10 are arranged at positions where the amount of penetration of the magnetic head 12 is secured.

As described above, in the present embodiment, as shown in FIG. 6, when the film front end 4a enters the film tunnel in which the film 4 is loaded from the film cartridge 22, the film front end 4a rubs against the film. A plurality of large protrusions 10 having a larger contact area with the film 4 than the small protrusions 8 are formed at the portions to be formed, and the bent portion of the film 4 generated when the film 4 is wound by the spool 24 causes the film pressure plate 2 to move. A plurality of the large protrusions 10 were also formed on the portion to be rubbed. As a result, it is possible to realize a film pressure plate that is less likely to be worn and shaved than a film pressure plate that has a spherical projection having a small contact area or has a large interval between the projections.

Further, since the plurality of smooth surfaces 10a of the large projections 10 are discontinuously provided in the film width direction, dust due to abrasion or the like is unlikely to remain on the film surface side of the film pressure plate 2.
Therefore, the film 4 is less likely to be scratched, and the magnetic head 12 and the film 4 are surely in contact with each other, so that highly reliable magnetic recording and reproduction can be performed.

That is, the film pressure plate of the present embodiment is a film pressure plate having a magnetic head attached to the film surface side, and the top is formed on the same plane at the center of the film pressure plate on the film surface side (corresponding to the screen size). A large number of small projections are formed, and the left and right peripheral parts outside the screen size of the film pressure plate are discontinuous in the film width direction and have the tops on the same plane as the tops of the above small projections, and the contact area is larger than the small projections. Since the plurality of large protrusions are provided, the flatness of the film can be ensured, and at the periphery of the pressure plate, the abrasion due to the running of the film can be reduced and the film can be prevented from being scratched.

Further, even if dust is generated due to the above-mentioned wear, the smooth surface of the large protrusion is discontinuous in the width direction of the film, so that the dust is unlikely to remain on the film surface due to running of the film. Therefore, the defective contact between the magnetic head and the film is less likely to occur, and good recording / reproduction of magnetic data can be performed.

In the present embodiment, if the layout is such that the bent portions of the film do not exist in the left and right peripheral portions of the film pressure plate 2, only the spool side of the film pressure plate 2 as shown in FIGS. 7 and 8. Alternatively, the large protrusion 10 may be formed only on the film cartridge side. Also,
As shown in FIG. 9, the large protrusions 10 have a spherical shape 30a as shown in the cross section CC in the film width direction and a trapezoidal shape 30b as shown in the cross section DD in the film running direction. Is provided, the contact area between the film 4 and the film pressure plate 2 is not extremely reduced and the film 4
The running resistance of can be reduced.

According to the above embodiment of the present invention, the following configuration can be obtained. (1) In a film pressure plate of a camera with a magnetic recording unit in which a magnetic head for recording and reproducing magnetic information on a film with a magnetic recording unit is provided on the film contact surface side, the film contact of the film pressure plate corresponds to the shooting screen size. A large number of small projections whose tops form the same plane at the center of the surface, and discontinuous in the film width direction at least on the cartridge chamber side peripheral portion of the film pressure plate, and in the same plane as the tops of the small projections. A plurality of protrusions having a contact area larger than that of the small protrusions, and a film pressure plate for a camera with a magnetic recording unit. (2) In a film pressure plate of a camera with a magnetic recording unit in which a magnetic head for recording and reproducing magnetic information on a film with a magnetic recording unit is provided on the film contact surface side, the film contact plate of the film pressure plate corresponds to the shooting screen size. A large number of small projections whose tops form the same plane in the center of the surface, and a discontinuity in the film width direction on the cartridge chamber side of the film pressure plate or on the winding spool chamber side peripheral part, A film pressure plate for a camera with a magnetic recording unit, comprising: a plurality of protrusions that are in the same plane and have a larger contact area than the small protrusions. (3) The film pressure plate for a camera with a magnetic recording unit according to (1) or (2), which is formed of a plastic or metal material.

[0023]

As described above, according to the present invention, while ensuring the flatness of the film, dust and scratches on the film caused by abrasion of the peripheral portion of the film pressure plate are reduced, and the magnetic generated by the dust due to abrasion is reduced. By reducing the contact failure between the head and the film, it is possible to provide a film pressure plate for a camera with a magnetic information recording unit that can perform highly reliable magnetic recording and reproduction.

[Brief description of drawings]

FIG. 1 is a perspective view showing a structure of a film pressure plate of a camera with a magnetic recording unit.

FIG. 2 is a front view of the film pressure plate seen from the film surface side.

FIG. 3 is a cross-sectional view for explaining a use state when a camera to which the film pressure plate is applied is cut in a vertical direction.

FIG. 4 is a cross-sectional view for explaining a usage state when the camera to which the film pressure plate is applied is laterally cut.

FIG. 5 is a diagram showing a shape of a large protrusion.

FIG. 6 is a diagram showing a state in which the leading end of the film comes into contact with the peripheral portion of the film pressure plate on the cartridge side.

FIG. 7 is a diagram showing a film pressure plate in which a large protrusion is formed only on the spool side.

FIG. 8 is a diagram showing a film pressure plate in which a large protrusion is formed only on the film cartridge side.

FIG. 9 is a view showing a shape of a modified example of the large protrusion 10.

[Explanation of symbols]

 2 film pressure plate 2b screw hole 2c film pressure plate surface 4 film 6 camera body 8 small protrusion 10 large protrusion 10a smooth surface 10b slope 12 magnetic head 14 pad 16 elastic member 18 screw 20 exterior member 22 film cartridge 24 spool

Claims (3)

[Claims] 1. A film having a magnetic track is used,
In a film pressure plate of a camera capable of magnetically recording photographing information on the magnetic track, a magnetic head arranged at a predetermined position on the film contact surface side for performing magnetic recording on the film, and a magnetic head arranged in the film contact surface at the top. A number of primary projections that share the envelope surface, and are located outside the shooting screen area and in the film width direction around the edge in the film feeding direction within the film contact surface and share the top envelope surface with the primary projections. And a plurality of second protrusions having a contact area with the film larger than the contact area of the first protrusion with the film. 2. The film pressure plate for a camera with a magnetic recording unit according to claim 1, wherein the second protrusion has a shape obtained by extending the first protrusion in the film feeding direction. 3. The film pressure plate for a camera with a magnetic recording unit according to claim 1, wherein the first protrusions are uniformly arranged in a grid pattern at a predetermined pitch on the film contact surface side. .