JPH0524898Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a film information detection device, and particularly to a film information detection device for detecting a film information pattern on the outer periphery of a film cartridge.

<Prior Art> Conventionally, this type of device detects a pattern 2 provided on the outer periphery of a cartridge 1 as shown in FIG.
Some have contacts.

<Problems to be solved by the invention> The current information pattern on the outer periphery of the cartridge detects conduction and non-conduction with respect to the reference pattern, but due to the instability of the surface condition, it is difficult to detect continuity with only one point of contact with the pattern. Accurate information detection is difficult.

For the reasons mentioned above, the one-pattern, one-contact type lacks reliability in information detection. In order to improve the reliability of information detection, there are two-contact types in one pattern, but these have twice the number of independent contact mechanisms, which reduces assembly workability and increases costs. Furthermore, there is a pitch limit in providing two independent contacts, and there is also a risk that the contacts may come into contact with other patterns due to displacement of the cartridge.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the prior art and provide a film information detection device with a simple mechanism and high reliability.

<Means for Solving the Problems> The structure of the present invention for achieving the above-mentioned object will be explained using FIG. 1 and FIGS. 2a and 2b, which correspond to embodiments.

The present invention is a film information detecting device for detecting a film information pattern on the outer periphery of a film cassette 1, in which the contact surface of a contact member 5 that contacts the outer periphery of the film cassette 1 is formed with a ring-shaped protrusion 5a. Furthermore, the coiled spring 6 enters into the hollow interior of the contact member 5, is positioned by the ring-shaped recess 5d on the back side of the ring-shaped projection 5a, and presses the contact member 5.

<Function> Since the contact member 5 is attached to a predetermined position by being biased by a spring so as to protrude from the inner surface of the cartridge chamber of the camera body, when the film cartridge 1 is loaded in the cartridge chamber, the cross section shown in FIG. As shown in the plan view and the longitudinal cross-sectional view of FIG. 2b, the ring-shaped protrusion 5a of the contact member 5 and the film information pattern 2 on the outer periphery of the film cassette 1 make contact at two points P ₁ and P ₂ .

Therefore, even if a contact failure occurs due to an error factor such as the tilt of the film cartridge 1 or an unstable surface condition of the film information pattern, the above-mentioned
Two-point contact between P ₁ and P ₂ can be reliably guaranteed, and the reliability of signal transmission can be improved.

In addition, the coiled spring 6 enters into the hollow interior of the contact member 5 and presses the position of the ring-shaped recess 5d on the back side of the ring-shaped projection 5a.
Since the effective length of the spring 6 can be made long and the spring constant can be made small even if the device is made compact, it is possible to stabilize (make constant) the spring pressure. Therefore, it is possible to prevent the spring pressure from being too strong and damaging the surface of the film information pattern, and conversely from causing contact failure due to the contact pressure being too small. Furthermore, since the position of the pressing part of the coiled spring is stabilized by the ring-shaped recess, it is possible to prevent the problem of the pressing part deforming erratically when compressed and changing the pressing direction or pressing position. can.

<Example> Hereinafter, an example of the present invention will be described based on FIGS. 1 to 4.

The film information detection device includes a holding frame 3, a contact holding member 4, a contact member 5, a spring 6, a spring regulating member 7,
The flexible printed circuit board 8 and the holding plate 9 are constructed as a unit.

The inner surface of the holding frame 3 has an arcuate surface that matches the inner surface of the cartridge chamber of the camera body 11, and a sliding opening 3a into which the contact holding part 4a of the contact holding member 4 is fitted is provided in the middle part thereof. On the outer surface thereof, engaging protrusions 3b are provided at the four corners, and positioning bosses 3c are provided on both the upper and lower sides. The contact holding member 4 is made of an insulating material, and a plurality of (six in the illustrated example) contact holding holes 4b are arranged in a line in the contact holding portion 4a. The contact member 5 is formed into a cap shape by drawing a metal plate, and has a ring-shaped projection 5a and a recess 5b having a substantially rounded shape at its tip, and a hollow portion 5c into which a coiled spring 6 is inserted. A plurality of them (six in the illustrated example) are provided. The pressing end of the coiled spring 6 is provided so as to press the ring-shaped recess 5d on the back side of the ring-shaped projection 5a of the contact member 5. The spring regulating member 7 is made of an insulating material, and a positioning hole 7a that fits with the positioning boss 3c of the holding frame 3 and a plurality of (six in the illustrated example) spring regulating holes 7b are arranged in a row at both upper and lower ends thereof. It is set up. The flexible printed circuit board 8 has a pattern portion 8 at one end thereof.
a and a pair of mounting holes 8b, the pair of mounting holes 8b
b is positioned by a pair of protrusions 9a protruding from one end of the inner surface of the holding plate 9, and is bonded to the holding plate 9. The holding plate 9 is made of a thin metal plate, and the protrusions 9a are formed by half-blanking, and the upper and lower sides of one end thereof have engaging protrusions 3b and positioning bosses 3c of the holding frame 3, respectively. A portion 9b and a positioning hole 9c are formed, and furthermore, screw holes 9d for attaching to the camera body 11 with screws 10 and positioning holes 9e that engage with the positioning boss 11a of the camera body 11 are provided on both upper and lower sides. .

Therefore, in the assembly structure of this film information detection device, a contact holding member 4 is inserted into the sliding opening 3a of the holding frame 3.
The contact holding portions 4a are fitted, and the contact members 5 are respectively inserted into the six contact member holding holes 4b.
Next, the positioning boss 3c of the holding frame 3 and the positioning hole 7a of the spring regulating member 7 are aligned, the spring regulating member 7 is attached, and the hollow part 5c of the contact member 5 is passed through the six spring regulating holes 7b of the spring regulating member 7. Insert a coiled spring 6 into each. In this case, the mounting height of the spring regulating member 7 is regulated by the holding frame 3, and its plate thickness is set larger than the pitch of the spring 6, so that the spring 6 is not caught in the spring regulating hole 7c. The length of the spring 6 is such that one end thereof protrudes outward from the spring regulating hole 7c.
Next, the holding plate 9 to which the flexible printed circuit board 8 is adhered is positioned by its positioning hole 9c and the positioning boss 3c of the holding frame 3, and is attached to the holding frame 3. In this case, the spring 6 is compressed, and the engagement protrusion 3b of the holding frame 3 is elastically deformed by contact with the engagement part 9b of the holding plate 9, and when pushed to a predetermined position, the engagement protrusion 3b and the engagement part 9b is completed and becomes a unit. This unit is installed so that the holding frame 3 fits into the opening 11b of the cartridge chamber of the camera body 11, and is positioned using the positioning boss 11a of the camera body 11 and the positioning hole 9e of the holding plate 9, and screwed with the screw 10. It is fixed to the camera body 11 through the hole 9d, and the assembly is completed as shown in FIG.

In the attached state of the camera body 11 shown in FIG. The contact member 5 is urged by a spring 6 to protrude toward the center of the cartridge chamber of the camera body 11, and one end of the spring 6 abuts against the ring-shaped recess 5d of the hollow portion 5c of the contact member 5. It is also positioned with a predetermined gap in the radial direction, and the other end contacts the pattern portion 8a of the flexible printed circuit board 8 and is held by the rigidity of the retaining plate 9, and its displacement in the radial direction is regulated by the spring regulating hole 7b of the spring regulating member 7. ing.

Therefore, when the film cartridge 1 shown in FIG. 5 is loaded in the cartridge chamber of the camera body 11 as shown in FIG. It is pushed in by the outer circumference of the part 2. At this time, the contact holding member 4 regulates the amount of protrusion of the contact member 5 when the film cartridge is not loaded as shown in FIG. 1, but is designed to prevent the contact member 5 from being caught when the film cartridge is loaded. . The contact holding member 4 and the contact member 5 are pushed in and come into contact with the spring regulating member 7, respectively, and there is no risk of damage to the pattern portion 8a due to direct contact with the flexible printed circuit board 8. Furthermore, since the spring regulating hole 7b of the spring regulating member 7 has the effect of regulating the displacement of the abutting end of the spring 6 with the pattern portion 8a, the reliability of electrical continuity and the reliability of the movement of the contact member 5 are improved. It is valid. Also,
The electrical conduction system is connected to the film information pattern 2→contact member 5→spring 6→pattern portion 8a, and a required film information signal is transmitted.

Here, the contact state between the film information pattern 2 portion of the film cartridge 1 and the contact member 5 is the second.
As shown in Figures a and b, a spring 6 is in contact with the inner surface of a ring-shaped protrusion 5a at the tip of the contact member 5, and the ring-shaped protrusion 5a and the film information pattern are connected to the contact points _P1 and _P2 . This is a two-point contact. Therefore, by providing play in the contact member 5 and the contact holding portion 4a of the contact holding member 4, even if an error factor such as the tilt of the film cartridge 1 occurs, the contact will not be lost.
Two-point contact between P ₁ and P ₂ can be ensured, and since the ring-shaped protrusion 5a of the contact member 5 has an R shape, the reliability of signal transmission can be improved without damaging the film information pattern of the film cassette 1. It becomes possible to improve the performance. In addition, a coiled spring 6
enters into the hollow interior of the contact member 5 and presses the ring-shaped recess 5d, so the effective length of the spring 6 can be increased, the spring constant (change in spring pressure with respect to displacement) can be reduced, and the spring pressure can be reduced. It is possible to prevent the contact pressure from becoming too large and damaging the film information pattern, and conversely, it is possible to prevent the contact pressure from being too small resulting in poor contact. Furthermore, since the pressing end of the coiled spring 6 is positioned by the ring-shaped recess 5d, it is possible to prevent misalignment and shaky deformation due to compression.
Can always provide stable contact pressure.

<Effects of the invention> As explained above, the present invention has two ring-shaped protrusions for one film information pattern of the film cassette by forming a ring-shaped protrusion on the contact end of the contact member.
Point contact is made possible, and the pitch of the two-point contact can be made small, so that the tolerance range for positional deviation is increased, and a highly reliable film information detection device can be produced with a simple configuration and at low cost. In addition, the effective length of the coiled spring that presses the contact member can be made long to reduce the spring constant, and the pressing end is positioned by a ring-shaped recess, preventing misalignment and wobbling deformation due to compression. This means that stable contact pressure can be applied.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of an embodiment of the film information detection device for a camera according to the present invention, FIGS. 2a and 2b are explanatory diagrams of the state of contact of the contact member when loading a film cartridge, and a is a cross-sectional view. , b is a sectional view taken along the line A-A of a, FIG. 3 is a sectional view of the main part when loading a film cartridge, FIG. 4 is an exploded perspective view of the film information detection device, and FIG. 5 is an object of use of the present invention. FIG. 2 is a perspective view of a film cartridge having a film information pattern as shown in FIG. DESCRIPTION OF SYMBOLS 1... Film cartridge, 2... Film information pattern, 3... Holding frame, 4... Contact holding member, 5... Contact member, 5a... Ring-shaped protrusion, 5
b... recessed part, 5c... hollow part, 5d... ring-shaped depression, 6... spring, 7... spring regulating member, 8...
Flexible printed circuit board, 9... Holding plate, 11
...The camera body.

Claims (1)

[Scope of utility model registration request] A film information detection device for detecting a film information pattern on an outer periphery of a film cartridge, comprising: a contact member that contacts the outer periphery of the film cassette; and a coil spring that presses the contact member against the outer periphery of the film cassette; The contact portion is formed into a ring-shaped protrusion and has a hollow interior, and one end of the coil spring enters into the hollow interior of the contact member, and is positioned in a ring-shaped recess on the back side of the contact member. 1. A film information detection device characterized in that the film information detection device is formed so as to be pressed.