JPH04285946A - Camera using film with magnetic storage part - Google Patents

Abstract

PURPOSE:To prevent the intrusion of noise to a second signal-pattern from the signal output terminal of a magnetic head to the signal input terminal of an amplifying circuit used for amplifying the output signal, to prevent the intrusion of the noise to each of the elements of the above-mentioned amplifying circuit, etc., from between the film pressing plate and the printed board and to accurately read the information. CONSTITUTION:The second signal-pattern for which the output terminal of the magnetic head is connected by a through hole plating from a soldered first pattern and the output signal of the magnetic head from the first signal is led to the amplifying circuit 12 is formed on the surface of the film pressing plate 1 side of the printed board 5. A ground pattern 5a, with a shape covering at least the second signal-pattern, is formed on the opposite surface to the film pressing plate. Also, recessed parts 1a are formed on the parts facing the elements 12, 13 and 21 on the printed board of the film pressing plate, so as to firmly attach the film pressing plate and the print substrate to each other.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera using a film with a magnetic storage section, which is equipped with a magnetic head for reading information from a magnetic storage section provided on the film.

0002

[Prior Art] Conventionally, a camera that uses a film equipped with a magnetic storage section and allows recording of photographing information, date, etc. on the magnetic storage section using a magnetic head, or reading information from the magnetic head, has been patented in the United States. It has been proposed in No. 4860037 and the like.

0003

[Problems to be Solved by the Invention] However, in this type of camera, electrical noise from the outside affects the signal pattern from the signal output terminal of the magnetic head to the signal input terminal of the amplifier circuit that amplifies the output signal. There is a problem in that the film tends to stick to the film, leading to errors in reading information written in the magnetic storage section of the film.

In view of the above points, an object of the present invention is to prevent noise from entering the second signal pattern from the signal output terminal of the magnetic head to the signal input terminal of the amplifier circuit that amplifies the output signal; It is an object of the present invention to provide a camera using a film with a magnetic storage part, which can prevent noise from entering each element such as the amplifier circuit between a film pressure plate and a printed circuit board, and can read information accurately.

[0005]

[Means for Solving the Problems] The present invention provides an output terminal of a magnetic head connected to the surface of a printed circuit board on the film pressure plate side from a first signal pattern soldered by through-hole plating, A second signal pattern is formed to guide the output signal of the magnetic head from the first signal pattern to the amplifier circuit, and the second signal pattern is formed on the opposite side to the film pressure plate side. A ground pattern having a shape that at least covers the ground pattern is formed, and concave portions are formed in the portions of the film pressure plate facing each element on the printed circuit board so that the film pressure plate and the printed circuit board can be attached in close contact with each other.

[0006]

[Function] A ground pattern is installed on the opposite side of the printed circuit board from the film pressure plate side to prevent noise from entering the second signal pattern, which is likely to cause errors in reading information. In addition, recesses are formed in the portions of the film pressure plate facing the respective elements on the printed circuit board so that the film pressure plate and the printed circuit board can be attached in close contact with each other.

[0007]

Embodiment FIGS. 1 to 5 show a first embodiment of the present invention, and FIG. 1 is a perspective view of a pressure plate, a printed circuit board, etc.
2 is a longitudinal sectional view of FIG. 1, FIG. 3 is a plan view of the printed circuit board on the side opposite to the pressure plate, FIG. 4 is a plan view of the printed circuit board and electric element as seen from the surface on the pressure plate side, and FIG. FIG. 2 is an electrical circuit diagram.

Reference numeral 1 denotes a film pressure plate, 2 a film with a magnetic memory part formed on the side of the film pressure plate 1 and fed by a known film feeding mechanism in the direction of arrow A in FIG. 1, and 3 a camera body. , 4 is a magnetic head that comes into sliding contact with the magnetic storage section of the film 2 to write or read information, and as shown in FIG.
and the film pressure plate 1, and the magnetic head 4 is configured to come into sliding contact with the film 2 at that time.

Reference numeral 5 denotes a printed circuit board, which is fixed to the film pressure plate 1 by screws 6 and 7.

Reference numerals 8, 9, 10, and 11 are lead wires, one end (not shown) of the lead wire 8 is connected to the ground circuit, and one end (not shown) of the lead wire 9 is connected to the power supply circuit. One ends (not shown) of the lines 10 and 11 are respectively connected to a control circuit of the camera. Also, the other end of the lead wire 8 is a signal pattern (conductive pattern).
5a-1, the other end of the lead wire 9 is connected to the signal pattern 5b, the other end of the lead wire 10 is connected to the signal pattern 5c, and the lead wire 11 is connected to the signal pattern 5c.
The other ends are soldered to the signal patterns 5d, respectively.

4a and 4b are output terminals of the magnetic head 4;
They are soldered to signal patterns 5e and 5f, respectively.

12 is an amplifier circuit such as Texas Instruments TL592B, 13, 14, 15,
16 and 17 are chip resistors, and 18, 19, 20, and 21 are chip jumpers, the circuit configuration of which is shown in FIG.

In FIGS. 3 and 4, the signal pattern 5g
is 5i, signal pattern 5h is 5j, and signal pattern 5 is
The signal pattern u is electrically connected to 5m, the signal pattern 5t is electrically connected to 5n, the signal pattern 5s is electrically connected to 5p, and the signal pattern 5r is electrically connected to 5q by through-hole plating. in this case,
In particular, external noise affects the circuit between the output section of the magnetic head 4 and the input terminal of the amplifier circuit 12, that is, the signal patterns 5e to 5l and the signal pattern 5.
It is between f and 5k.

In this embodiment, the signal patterns 5g, 5h are printed on the film near the soldered portions of the output terminals 4a, 4b of the magnetic head 4 and the signal patterns 5e, 5f, that is, at the signal patterns 5g, 5h. It is moved to the pressure plate 1 side by a through hole, and a ground pattern 5a is provided on the side opposite to the film pressure plate 1 side to shield the signal pattern part and prevent noise from the outside. I'm trying to block it.

Regarding the noise that enters this circuit from the film pressure plate 1 side, the camera has metal members such as the shutter base plate and lens barrel base plate on the film 2 side, and because of these base plates, it is difficult to communicate with the outside world. Since the distance is maintained at a certain level or more, the influence of noise is relatively low.

Further, if there is a gap between the printed circuit board 5 and the film pressure plate 1, noise will enter from there, so the printed board 5 and the film pressure plate 1 are brought into close contact with each other. For this reason,
A recess 1a is provided in a portion of the film pressure plate 1 facing elements such as the amplifier circuit 12 and the chip jumper 21 (see FIG. 2).
, so that there is no problem even if these elements and the film pressure plate 1 are pressed into contact with each other.

Furthermore, the periphery of each concave portion 1a of the film pressure plate 1 is formed into an inclined surface. This is because when molded with plastic, sudden differences in wall thickness can cause deformation and sink marks.
The thickness changes gradually. In addition to screws, double-sided tape,
Adhesive etc. may also be used.

FIG. 6 is a longitudinal sectional view of the main parts of the second embodiment of the present invention, in which the same parts as in the first embodiment are given the same reference numerals.

In this embodiment, a conductive paint is applied to the surface of the film pressure plate 1 on the side that is in close contact with the printed circuit board 5, thereby completely shielding elements such as the amplifier circuit 12 and the chip jumper 21. becomes possible. Of course, this conductive surface and the ground of the printed circuit board 5 are electrically connected.

Therefore, even if the film pressure plate 1 is made of plastic material, the same effect as that of a metal film pressure plate can be obtained. Furthermore, instead of conductive paint, plating with nickel or the like may be used.

According to each of the above embodiments, the amplifier circuit 12
Noise from each element and the outside affects the circuit,
The area between the output part of the magnetic head 4 and the input terminal of the amplifier circuit 12 is formed on the film pressure plate 1 side of the printed circuit board 5, and a ground pattern is formed on the side opposite to the film 2 side. At the same time, each element disposed on the film pressure plate 1 side is placed in a recess 1 provided in the film pressure plate 1.
a, and the film pressure plate 1 and the printed circuit board 5 are brought into close contact with each other, so that noise from the outside may be picked up between the output section of the magnetic head 4 and the input terminal of the amplifier circuit 12, and the film pressure plate 1 and the printed circuit board 5 may be in close contact with each other. Noise is no longer introduced between the printed circuit board 5 and the information is read out incorrectly.

Furthermore, since each element arranged on the printed circuit board 5 is placed in the recess 1a provided in the film pressure plate 1 as described above, the space can be used effectively.

[0023]

[Effects of the Invention] As explained above, according to the present invention,
A second signal pattern is installed on the opposite side of the printed circuit board from the film pressure plate side, which is likely to cause errors in reading information.
In order to form a ground pattern to prevent noise from entering the circuit board, and to allow the film pressure plate and printed circuit board to be attached in close contact, recesses are formed in the portions of the film pressure plate facing each element on the printed circuit board. is forming. This prevents noise from entering the second signal pattern from the signal output terminal of the magnetic head to the signal input terminal of the amplifier circuit that amplifies the output signal, and from entering the amplifier circuit between the film pressure plate and the printed circuit board. It is possible to prevent noise from entering each element, and it is possible to read information accurately.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the main parts of a camera in a first embodiment of the present invention.

FIG. 2 is a longitudinal cross-sectional view of FIG. 1;

FIG. 3 is a plan view of the printed circuit board according to the first embodiment of the present invention, viewed from the side opposite to the film pressure plate.

FIG. 4 is a plan view of the printed circuit board and electric element in the first embodiment of the present invention, viewed from the film pressure plate side.

FIG. 5 is an electrical circuit diagram shown in FIG. 4;

FIG. 6 is a longitudinal sectional view showing the main parts of a camera in a second embodiment of the invention.

[Explanation of sign]

1 Film pressure plate 1a Concave portion 2 Film 4 Magnetic head 5 Printed circuit board 5a Ground patterns 5b to 5n, 5p to u Signal pattern 12 Amplifier circuits 13 to 17 Chip resistors 18 to 21 Chip jumper

Claims (1)

[Claims] 1. A magnetic head attached to a film pressure plate and reading information from a magnetic storage section of the film;
An output terminal of the magnetic head is soldered to a first signal pattern provided on the opposite side to the film pressure plate, and an amplifier circuit or the like for amplifying the output signal of the magnetic head is provided on the film pressure plate side. A camera using a film with a magnetic memory unit, comprising a printed circuit board on which each element is provided, the output terminal of the magnetic head being soldered to a surface of the printed circuit board on the film pressure plate side. A second signal pattern is formed which is connected by through-hole plating from the signal pattern of the first signal pattern to guide the output signal of the magnetic head from the first signal pattern to the amplifier circuit, and A ground pattern having a shape that at least covers the second signal pattern is formed on a surface opposite to the second signal pattern, and the film pressure plate is attached so that the film pressure plate and the printed circuit board can be attached in close contact with each other. A camera using a film with a magnetic memory section, characterized in that a recess is formed in a portion facing each element on the printed circuit board.