JPH11103136A - Mounting structure of flexible printed board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting structure of a flexible printed wiring board, which is capable of securing space for connection with other circuit board within a camera and the mounting of electric circuit components. SOLUTION: In a camera, where at least one sheet of large-sized flexible printed board to mount main electric circuit components is mounted, a first face 31 of a large-sized flexible printed board 20 has a connection 25 with the main body circuit being positioned at the lowermost layer within the large- sized flexible printed board, and a second face 32 is bent roughly 180 deg. from the first face, along the first bending line. Furthermore, the comera has an electric circuit mounting part 102, and the third face 33 is bent roughly by 180 deg. along the second bending line and moreover has an connection 26 with other electric circuit positioned in the upper layer part of the camera, and a fourth face 34 is extended from a third face and has an electric circuit mounting part arranged in front of the camera, and a fifth face 35 is extended from the third face, and has an electric circuit part arranged at a penta prism part, so that a first bending line L1 and a second bending line L2 are in relation of being roughly orthogonal to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric circuit mounting structure of a camera, and more particularly to a mounting structure of a flexible printed circuit board in a single-lens reflex camera or the like.

[0002]

2. Description of the Related Art In recent years, high-density electric circuit mounting is realized by making full use of a flexible printed circuit board in order to perform high-precision and multifunctional automation.

[0003] However, the size of the electric circuit tends to be larger and more complicated, but it is desired that the size of the camera be smaller. Along with this, further ingenuity has been required for a mounting structure using a flexible printed circuit board. As a method of improving the mounting structure, there is a method of mounting the circuit board by dividing it.

However, with the enlargement of electric circuits,
Since the number of connection signals between the main electric components increases, the number of connection signals between the circuit boards becomes enormous in the mounting structure in which the circuit boards are divided. As a result, a large space is required for connection between the substrates, which leads to a decrease in the mounting density. Furthermore, as the number of inter-substrate connections increases, it becomes more difficult to guarantee reliability. Furthermore, the connection parts are required to be larger and have higher reliability, resulting in a significant increase in cost.

Therefore, it is desirable to mount main electric circuit components on one large flexible printed circuit board as much as possible, and to complete the wiring of connection signals between the electric circuit components within the large flexible printed circuit board.

Many applications have been filed in the past to realize such an electric circuit mounting structure. For example, as shown in Japanese Utility Model Application Laid-Open No. 63-113135, there is an electric circuit mounting structure excellent in space efficiency.

In this invention, a single large-sized flexible printed circuit board is efficiently disposed in a camera, but a path from a mirror box portion and a front surface of a main body to a camera upper layer surface extends from a mirror box side surface to a pentaprism portion. It has a structure that goes through a route.

In the case of a large-scale electric circuit, even if the main electric circuit can be integrated on one large-sized flexible printed circuit board, various peripheral electric circuits must still be mounted on a separate small-sized flexible printed circuit board. It is becoming. Therefore, it is necessary to provide a means for connecting the above-mentioned large-sized flexible printed circuit board on which the main electric circuit is mounted and the small-sized flexible printed circuit board.

In this conventional device, another small-sized flexible printed circuit board on which peripheral circuits which cannot be integrated on a large-sized flexible printed circuit board are connected to a large-sized flexible printed circuit board at an end portion of the large-sized flexible printed circuit board. Further, from the aspect of component mounting of the flexible printed board, it is generally advantageous that the component mounting surface is integrated on the same surface. Because components mounting on a flexible printed circuit board is usually performed by a mounter that places electrical components and automatic mounting equipment such as a reflow furnace that solders them, component mounting is completed in one process if integrated on the same surface Because it is done. However, in this invention, main electric components are distributed and arranged on both front and back surfaces of a large-sized flexible printed circuit board.

[0010]

According to the prior art, the following problems occur.

First, dispersing main electric circuit components on a plurality of circuit boards in order to mount a large-scale electric circuit in a camera requires a reduction in mounting density and reliability as described above.
Further, the cost is significantly increased.

In the above-described conventional example in which an electric circuit mounting structure using a large-sized flexible printed circuit board is realized, main electric circuit components are mounted on a mirror box portion and a front surface of a main body, and a path reaching an upper layer surface of the camera is formed on a side surface of the mirror box. It has a structure that passes through a path from to the pentaprism section.

For this reason, all the wiring from the main electric circuit parts to other electric parts located in the upper layer of the camera passes through the path from the side surface of the mirror box to the pentaprism part, and there is a large space restriction.

Therefore, it is difficult to mount a further large-scale electric circuit on a wiring space and a component mounting space.

In order to increase the mounting area of the circuit components in the camera, the circuit board must necessarily have a hierarchical structure of a plurality of stages. However, in the conventional example, the extended portion of the flexible printed circuit board folded back at the pentaprism portion has two portions at the pentaprism portion and the upper portion of the spool chamber.
Only a hierarchical structure is formed, and a two-layer structure is formed at a place far away from the main circuit components.

If the large flexible printed circuit board on which the main electric circuit is mounted and the other small flexible printed circuit board on which the peripheral electric circuit is connected are at the end portions as in the conventional example, the connection is made from the main electric circuit parts. The distance to the part becomes long, and noise countermeasures and the like on the wiring route are required. In addition, the wiring density of the main electric circuit portion becomes abnormally high, resulting in complicated wiring.

Further, according to the above-mentioned conventional example, the main electric components are distributed and arranged on both the front and back surfaces of the large-sized flexible printed circuit board. This makes it difficult to guarantee reliability and increases costs.

A first problem to be solved by the present invention is as follows.
An object of the present invention is to provide a mounting structure of a flexible printed wiring board in which a hierarchical structure of a flexible printed circuit board in a camera is formed, and a connection space with other circuit boards and a mounting space for electric circuit components can be secured.

A second problem to be solved by the present invention is as follows.
An object of the present invention is to provide a mounting structure of a flexible printed circuit board which facilitates a connection operation with another flexible printed circuit board on which another electric circuit is mounted.

A third problem to be solved by the present invention is as follows.
An object of the present invention is to provide a mounting structure of a flexible printed circuit board that prevents electric signal lines required for connection with another flexible printed circuit board from intersecting and realizes efficient wiring.

A fourth problem to be solved by the present invention is as follows.
It is an object of the present invention to provide a flexible printed circuit board mounting structure capable of separating a large current meter and a large number of digital signal systems of a camera from an analog signal system concentrated on a lower portion of the camera and minimizing adverse effects due to noise. .

A fifth problem to be solved by the present invention is as follows.
An object of the present invention is to provide a mounting structure of a flexible printed circuit board, which can simplify a component mounting process of the flexible printed circuit board.

A sixth problem to be solved by the present invention is as follows.
An object of the present invention is to provide a mounting structure of a flexible printed circuit board in which a large ammeter and a large number of digital signal systems of a camera are separated from an analog signal system concentrated on a lower portion of the camera, and signal lines of both do not cross.

[0024]

According to the first aspect of the present invention, there is provided a camera having at least one large-sized flexible printed circuit board on which main electric circuit components are mounted. The large-sized flexible printed circuit board is a folded multi-layered flexible printed circuit board, and a first surface of the large-sized flexible printed circuit board is located at a lowermost layer in the large-sized flexible printed circuit board and is connected to a main unit circuit. Part, the second
The surface is bent approximately 180 degrees from the first surface along the first folding line, and has an electric circuit mounting portion, and the third surface is the second surface.
Is bent approximately 180 degrees from the second surface along the bending line, and has a connection portion with another electric circuit located in the upper layer of the camera, and the fourth surface is extended from the third surface and is disposed on the front surface of the camera. The fifth surface extends from the third surface and has an electric circuit mounting portion disposed on the pentaprism portion, and the first bending line and the second bending line are substantially mutually separated. It is characterized by having an orthogonal relationship.

In order to solve the second problem, according to the present invention, the second surface and the third surface of the large-sized flexible printed circuit board are located above the spool chamber of the camera. A reinforcing plate is disposed between the third surface and the third surface.

In order to solve the third problem, the present invention according to claim 3 is characterized in that a large-sized main electric circuit component is mounted on the second and fourth surfaces of a large-sized flexible printed circuit board. And

According to a fourth aspect of the present invention, a large-sized main electric circuit component mounted on the second surface of a large-sized flexible printed board mainly controls non-analog signals. And a large-sized main electric circuit component mounted on the fourth surface of the large-sized flexible printed circuit board is a CPU that mainly controls analog signals.

In order to solve the fifth problem, according to the present invention, when a large-sized flexible printed circuit board is developed, the first surface, the second surface, the third surface, the fourth surface, and the fifth surface are developed. Are characterized in that the component mounting surfaces are all the same.

According to a sixth aspect of the present invention, there is provided the present invention, wherein the sixth surface is provided by extending the fourth surface of the large-sized flexible printed circuit board, and the sixth surface is provided with an analog signal. And a CPU for mainly controlling non-analog signals on the second surface.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIGS. 1, 2 and 3 show a first embodiment of the present invention.

FIG. 1 is a front view of a camera showing a mounting structure of a flexible printed circuit board according to the present invention.

In FIG. 1, 1 is a camera body, 2 is a lens mount for attaching and detaching an interchangeable lens, and 3 is a pentaprism.

4 is a light control sensor for measuring reflected light from the film surface for flash light control, 5 is a focus detection sensor for detecting the distance to the subject, 6 is a main mirror and a finder optical including a pentaprism 3 System and focus detection sensor 5
It is movable to a first position for guiding a light beam to the first position and to a second position retracted from the photographing optical path for exposing the film.

Reference numeral 7 denotes a DX flexible printed circuit board connected to a unit for reading the DX code of the film cartridge.

Reference numeral 8 denotes a dimming flexible printed board on which the dimming sensor 4 and a peripheral circuit (not shown) are mounted. Reference numeral 9 denotes an AF flexible printed board on which the focus detection sensor 5 and a peripheral circuit (not shown) are mounted.

Reference numeral 10 denotes a main body flexible printed circuit board configured as a camera main body unit.
3 are mounted on the control circuit component 11, and are also connected to a contact portion 12 with an external motor drive. Although not shown, the main body flexible printed circuit board 10 receives various operation switches, and further has a contact portion for a date imprinting back cover.

The motor 13 is a film feeding motor arranged in a spool chamber (not shown).

Reference numeral 20 denotes a large-sized flexible printed circuit board (hereinafter, referred to as a "main flexible printed circuit board") on which main electronic components such as a CPU for controlling the camera are mounted. , Further extended to the lower surface position of the main body 1,
Form one.

A flexible connector 2 is provided on the lower surface 21 of the main body.
2, 23, and 24 are mounted, and are connected to the DX flexible printed board 7, the dimming flexible printed board 8, and the AF flexible printed board 9, respectively.

On the upper surface of the spool chamber, a main body flexible printed board 10, a main flexible printed board 20 folded in a three-layer structure, and a display flexible printed board 40 are further arranged thereon from the bottom.

41 is a display flexible printed circuit board 40
A liquid crystal driver 42 is mounted on an external display liquid crystal.

The display flexible printed circuit board 40 has an extension 43 and is connected to the first display liquid crystal 14 in the finder. The external liquid crystal display 42 and the first display liquid crystal 14 in the finder are driven by the liquid crystal driver 41 described above.

Reference numeral 50 denotes an in-finder display flexible printed board connected to the second in-finder display liquid crystal 15.

FIG. 2 is a perspective view of the mounting structure of the flexible printed circuit board in the upper part of the spool chamber of the camera, as viewed obliquely from the back. Here, other structural components are omitted for easy understanding of the configuration of the flexible printed circuit board.

Reference numeral 20 denotes a main flexible printed circuit board on which most of the main circuit components are mounted.

Reference numeral 10 denotes a main body flexible printed circuit board configured as a camera main body unit.

The motor control circuit 11 is mounted on the main body flexible printed circuit board 10 as described above, and is also connected to a contact portion 12 with an external motor drive.
It also receives various operation switches and has a contact for a date imprinting back cover.

The main body flexible printed circuit board 10 has a connection arm 13 and is connected to a flexible connector 25 mounted on the main flexible printed circuit board 20 to copy signals for the motor control circuit, various operation switches and date. Signals for external accessories such as a back cover and a motor drive are electrically connected to the main flexible printed circuit board 20.

The flexible connector 25 is mounted on the upper surface of the first surface 31 of the main flexible printed circuit board 20 which is folded to form a multi-layer structure.

Reference numeral 32 denotes a second surface of the main flexible printed board 20 bent 180 degrees from the first surface 31 along the first bending line L1. The first bending line L1 is a line parallel to the photographing optical axis of the camera.

The first CPU 10 is provided on the lower surface side of the second surface 32.
1 and a plurality of other electric circuit components (not shown) are mounted to form a first main electric circuit mounting portion 102 of the camera indicated by oblique lines. The first CPU 101 is a CPU that also has a function of a liquid crystal driver for driving the second viewfinder display liquid crystal 15.

Reference numeral 33 denotes a third surface of the main flexible printed circuit board 20 bent 180 degrees from the second surface 32 along the second bending line L2. This second bending line L2 is a line parallel to the film surface.

On the upper surface of the third surface 33, a flexible connector 2 for connecting to another flexible printed circuit board is provided.
6 and 27 are implemented.

A support plate 28 is arranged between the second and third surfaces, and is supported and fixed to the camera body at a location (not shown).

Reference numeral 34 denotes a fourth surface of the main flexible printed circuit board 20 which extends from the third surface and covers the front surface of the camera. As shown in FIG.
U103 and a plurality of electric circuit components (not shown) are mounted to form a second main electric circuit mounting portion 104 of the camera indicated by oblique lines.

Reference numeral 35 denotes a fifth surface of the main flexible printed circuit board 20 which extends from the third surface 33 and is disposed along the pentaprism 3, on which other electric circuits (not shown) are mounted. .

Reference numeral 40 denotes a display flexible printed circuit board on which an external display liquid crystal 42 and a liquid crystal driver 41 for driving the first display liquid crystal 14 in the finder shown in FIG. 1 are mounted.

The display flexible printed circuit board 40 has an extension 4 connected to the display liquid crystal 14 in the first finder.
3 and a connecting arm 44 to the main flexible printed circuit board 20.

The connecting arm 44 is bent by 180 degrees and connected to the flexible connector 26 on the third surface 33 of the main flexible printed circuit board 20. Thus, communication of electric signals with a main electric circuit mounted on the main flexible printed circuit board 20 is performed.

The extension 43 is also connected to the first viewfinder display liquid crystal 14 at a point bent 180 degrees.

Reference numeral 50 denotes a display flexible printed circuit board in the finder connected to the second display liquid crystal 15 in the finder shown in FIG. 1. The connecting arm 51 is connected to the flexible connector 27 on the third surface 33 of the main flexible printed circuit board 20. It is connected to the. Thereby, the first CPU 101
Of the second viewfinder.

At the time of connection work to these flexible connectors 26 and 27, the display flexible printed circuit board 40 is maintained in a state of rising from the connection arm portion 44 and the extension portion 43 so that the flexible connector 26 can be seen by an operator. I have. Also, as can be seen from the figure, the third surface 33 of the main flexible printed circuit board 20 on which the flexible connectors 26 and 27 are mounted is located on the uppermost layer above the spool chamber.

The connection to the flexible connectors 26 and 27 is performed after the main flexible printed circuit board 20 is mounted on the camera body. At this time, since the support plate 28 is also assembled, the main flexible printed circuit board 20 is connected.
The flatness of the third surface 33 is sufficiently ensured. Therefore, the connection work to the flexible connectors 26 and 27 can be easily performed.

The signals and various operation switches for the control circuit of the motor connected to the flexible connector 25 mounted on the first surface 31 of the main flexible printed circuit board 20, and the outside of the date imprinting back cover, the motor drive and the like. Most of the signals for mounting accessories are on the second side 3
The processing is performed by a first main electric circuit mounting unit 102 including a first CPU 101 mounted on the second CPU 2.

The electric signals of the dimming flexible printed circuit board 8 and the AF flexible printed circuit board 9 connected by the flexible connectors 22 and 23 on the lower surface 21 of the main body shown in FIG. 1 include many analog signals. Most of these signals are transmitted to the second CP mounted on the fourth surface 34.
The processing is performed in the second main electric circuit mounting unit 104 including U103.

As described above, the first CPU 101 mounted on the second surface 32 is a CPU that mainly controls non-analog signals.
The main electric circuit mounting section 102 is an area mainly for processing non-analog signals.

A second CPU mounted on the fourth surface 34
103 is a CPU that mainly controls analog signals.
The main electric circuit mounting section 104 is an area that mainly processes analog signals.

FIG. 3 is an exploded view of the main flexible printed circuit board 20 of the present invention, showing the front side.

As described above, the non-analog system signal is
Most of the first, second, third, and third surfaces 32, 33, and 35 are concentrated on the fourth surface 34 and the lower surface 21 of the main body.

The main flexible printed circuit board 20
Flexible connectors 26 and 27 connected to a flexible printed circuit board other than the first CPU 101 and the second CPU
Since it is located between the signal lines 103, the signal lines for communication from both to the other flexible printed circuit board are also wires that minimize crossing each other.

A dashed line in FIG. 3 is a bending line of a main portion of the main flexible printed circuit board 20.

L1 is the distance between the first surface 31 and the second surface 32.
L2 is the second surface 32 and the third surface 3
3 is a 180 degree fold line.

L3 is a bending line of approximately 90 degrees between the third surface 33 and the fourth surface 34, and L4 is a bending line between the fourth surface 34 and the fifth surface 34.
A fold line of approximately 90 degrees between the surfaces 35.

Since the component mounting surface of the main flexible printed circuit board 20 is entirely mounted on the upper surface of the paper, the component mounting process is completed in one process.

(Second Embodiment) FIG. 4 is a developed view of the surface of a main flexible printed circuit board according to another embodiment of the present invention.

Here, an extension portion 36 corresponding to the fourth surface to the sixth surface of the main flexible printed circuit board 20 extends. This sixth surface is the fourth surface 3 when incorporated into the camera.
4 and is bent 180 degrees along the bending line L5.

On the sixth surface 36, a second main electric circuit mounting portion 104 including a second CPU 103 is mounted.

Even in such an arrangement, non-analog signals are transmitted to the first surface 31, the second surface 32, and the third surface 3 as described above.
Most of the signals are collected on the third and fifth surfaces 35, and analog signals are transmitted to the fourth surface 34, the sixth surface 36, and the lower surface 21 of the main body.
Most of them are gathered.

The main flexible printed circuit board 20
Flexible connectors 26 and 27 connected to a flexible printed circuit board other than the first CPU 101 and the second CPU
Since the point located between 103 is the same, the communication lines from both to the other flexible printed circuit board are also wirings which minimize crossing each other.

[0080]

According to the first aspect of the present invention, the hierarchical structure of the flexible printed circuit board in the camera is easily formed, so that the connection with other circuit boards and the mounting of the electric circuit components can be performed without carelessly increasing the size of the camera. Space can be secured and a large-scale electric circuit can be mounted.

According to the second aspect of the present invention, the flatness of the flexible printed circuit board during the assembling operation can be maintained, the connection operation with another flexible printed circuit board is facilitated, and the reliability is improved.

According to the third aspect of the present invention, it is possible to realize a non-wasteful wiring by minimizing electric signal lines required for connection with another flexible printed circuit board to cross each other.

According to the fourth aspect of the present invention, since a large number of digital signal systems and analog signal systems of the camera are separated, adverse effects due to noise can be minimized.

According to the fifth aspect of the present invention, since the component mounting surfaces of the large-sized flexible printed circuit board in the unfolded state are all the same, simplification of component mounting can be achieved and cost can be reduced.

According to the present invention, since a large number of digital signal systems and analog signal systems of the camera are separated from each other, adverse effects due to noise can be minimized.

[Brief description of the drawings]

FIG. 1 is a front view of a camera showing an embodiment of a mounting configuration of the present invention.

FIG. 2 is an oblique rear view of an embodiment of a mounting configuration of an upper portion of a spool chamber of the camera.

FIG. 3 is a developed surface view showing an embodiment of the main flexible printed circuit board of the present invention.

FIG. 4 is a surface development view of a main flexible printed circuit board according to another embodiment.

[Explanation of symbols]

 1: Camera body 2: Lens mount 3: Penta prism 4: Light control sensor 5: Focus detection sensor 6: Main mirror 7: DX flexible print board 8: Light control flexible print board 9: AF flexible print board 10: Body flexible print Substrate 11: Motor control circuit parts 12: Contact part with external motor drive 13: Motor 14: First display liquid crystal in viewfinder 15: Second display liquid crystal in viewfinder 20: Main flexible printed circuit board 21: Lower surface of main body 23, 24, 25, 26, 27: Flexible connector 28: Support plate 31: First surface of main flexible printed circuit board 32: Second surface of main flexible printed circuit board 33: Third surface of main flexible printed circuit board 34: Main flexible 4th surface of printed circuit board 35: Fifth surface of main flexible printed circuit board 36: Sixth surface of main flexible printed circuit board 40: Display flexible printed circuit board 41: LCD driver 42: External display liquid crystal 43: Extension unit 44: Connection arm unit 50: Display flexible in viewfinder Printed circuit board 51: connection arm 101: first CPU 102: first main electric circuit mounting unit 103: second CPU 104: second main electric circuit mounting unit L1: between first and second surfaces L2: Bending line between the second and third surfaces L3: Bending line between the third and fourth surfaces L4: Bending line between the fourth and fifth surfaces L5: Fourth surface Fold line between the third and sixth surfaces

Claims (6)

[Claims] 1. A camera mounted with at least one large-sized flexible printed circuit board on which main electric circuit components are mounted, wherein the large-sized flexible printed circuit board is a folded multi-layer flexible printed circuit board, The first surface of the printed circuit board is located at the lowermost layer in the large-sized flexible printed circuit board and has a connection portion with the main unit circuit, and the second surface is substantially 180 degrees from the first surface along the first folding line. The third surface is bent about 180 degrees from the second surface along the second bending line, and has a connection portion with another electric circuit located in the upper layer portion of the camera. The fourth surface is extended from the third surface and has an electric circuit mounting portion disposed on the front surface of the camera, and the fifth surface is extended from the third surface and disposed on the pentaprism portion. A flexible printed circuit board mounting structure comprising an electric circuit mounting portion, wherein the first bending line and the second bending line are substantially orthogonal to each other. 2. The large-sized flexible printed circuit board has a second surface and a third surface located above a spool chamber of the camera, and a reinforcing plate is disposed between the second surface and the third surface. The mounting structure for a flexible printed circuit board according to claim 1. 3. The flexible printed circuit board mounting structure according to claim 1, wherein large-sized main electric circuit components are mounted on the second and fourth surfaces of the large-sized flexible printed circuit board. 4. A large-sized main electric circuit component mounted on the second surface of the large-sized flexible printed circuit board is a CPU for mainly controlling non-analog signals, and is mounted on a fourth surface of the large-sized flexible printed circuit board. 4. The flexible printed circuit board mounting structure according to claim 3, wherein the large-sized main electric circuit component is a CPU that mainly controls analog signals. 5. The component mounting surface of a first surface, a second surface, a third surface, a fourth surface, and a fifth surface when the large-sized flexible printed circuit board is unfolded is the same surface. 2. The mounting structure of the flexible printed circuit board according to 1. 6. A sixth surface is provided by extending a fourth surface of the large-sized flexible printed circuit board, a CPU for mainly controlling analog signals is mounted on the sixth surface, and a non-analog system is mounted on the second surface. The flexible printed circuit board mounting structure according to claim 1, further comprising a CPU for mainly controlling signals.