JP2919677B2 - Flat-bed micro camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat-bed type micro camera for projecting a reduced image of a subject on a film sandwiched between an aperture mask and a flat plate.

[0002]

2. Description of the Related Art A film is sandwiched between an aperture mask (hereinafter simply referred to as a mask) perpendicular to the optical axis of a photographing lens and a pressure plate, and a reduced image of a subject by the photographing lens is projected on the film from a window of a frame formed on the mask. 2. Description of the Related Art Flat-bed type micro-cameras are known.

Here, the pressure plate can be pressed and separated from the mask, the film is fed with the pressure plate separated from the mask, and the film is fixed by pressing the pressure plate against the mask. The photographing is performed with the film fixed.

FIG. 7 is an exploded view showing the structure of a conventional drive roller 2 and a contact roller 3 for feeding a film 1. The film 1 is intermittently fed between the rollers 2 and 3. An annular groove 4 having a width substantially equal to the width of the film 1 is formed on the outer peripheral surface of the drive roller 2. The film 1 is engaged with the annular groove 4 and positioned in the width direction.

The contact roller 3 has a width substantially equal to the annular groove 4 and is pressed by a spring so as to be engaged with the annular groove 4. Therefore, when the drive roller 2 rotates, the film 1 sandwiched between the contact roller and the drive roller 2 is fed. The contact roller 3 is made of a metal and formed in a thick cylindrical shape, and is held on a support shaft 6 via a bush 5 made of a resin or the like pressed into the contact roller 3.

[0006]

Problems with the prior art Here, in the conventional contact roller, both edges are chamfered by the conical surface 3a. Therefore, a sharp edge 3b having an angle β with respect to the rotation axis F is formed at the intersection of the cylindrical surface of the contact roller 3 and the conical surface 3a. Therefore, when the contact roller 3 is pressed against the film 1 and rotated, the edge 3b generates a mark, that is, an indentation on the film 1, and there is a problem that the image quality of the microfilm deteriorates.

Further, since the conventional contact roller 3 is thick and heavy, it has a large moment of inertia and a large rotational friction resistance. As the film 1 is intermittently fed, all the other rollers such as the contact roller 3 and the tension roller intermittently rotate and stop intermittently. If the resistance is large, the rotation cannot follow the movement of the film 1 and rubs the surface of the film 1. This is one of the causes of scratching the film 1 and further deteriorating the image quality of the microfilm.

In particular, when chromium plating is applied to the surface of the contact roller 3 or the like, burrs due to this plating are likely to be generated on the edge 3b, so that it is necessary to remove the burrs.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and reduces the risk of indentation of the film when the contact roller rolls on the film. It is a first object of the present invention to provide a flat-bed type micro camera in which the possibility of causing scratches on the film is reduced.

It is another object of the present invention to provide a flat-bed micro camera in which, when chrome plating is performed on the surface of a contact roller, plating burrs do not occur on the film contact surface, and burrs are not required to be removed. This is the purpose of 2.

[0011]

According to the present invention, a first object is to form a reduced image of a subject by the photographing lens on the aperture mask by sandwiching a film between an aperture mask and a pressure plate perpendicular to the optical axis of the photographing lens. A flat roller type micro camera that projects the film through the frame window, and a drive roller having an annular groove formed therein for engaging the film and positioning the film in the width direction; and a drive roller formed of a hollow cylinder and engaged in the annular groove. And a contact roller for pressing the film against the drive roller, wherein the outer peripheral surface of the contact roller is a central portion formed of a cylindrical surface,
This is achieved by a flat-bed type micro camera characterized by being formed at both ends formed of a curved surface which is continuous with the center and whose tangent forms an axis of rotation with the rotation axis continuously increasing from the center.

A second object is to provide a contact roller,
This is achieved by forming a hollow cylinder made of aluminum whose surface is chrome-plated and supporting it on a spindle by roller bearings.

[0013]

FIG. 1 is an external perspective view of a flat-bed type micro camera,
2 is a front view showing the internal structure of the camera, FIG. 3 is an enlarged perspective view near the mask, and FIG. 4 is an exploded perspective view near the pressure plate.

In FIG. 1, reference numeral 10 denotes a stand, and 12 denotes a horizontal photographing plate. A subject such as an original is placed in accordance with a corner mark of the photographing plate 12. On the stand 10, a column 14 stands vertically from the back side of the photographing plate 12, and a camera platform 16 is mounted on the column 14 so as to be able to move up and down. The camera mounting table 16 is fixed at a predetermined height in accordance with the image reduction ratio.

A photographing lens 18 (see FIG. 1) is fixed to the camera mount 16 vertically toward the photographing plate 12. A camera head 20 is mounted on the upper surface. The camera head 20 is rotatable around the optical axis of the lens 18, that is, the vertical axis, and can be fixed by tightening the lock lever 22.

Reference numeral 24 denotes an automatic exposure apparatus, 26 denotes a lamp cover having a built-in illumination lamp, 28 denotes a display panel, and 30 denotes a control panel. On the display panel 28, an operation status such as a frame size and a photographing operation is displayed. In the control panel 30, various settings such as setting of film sensitivity, number and mode for printing on the film, and the like are performed.

Next, the configuration inside the camera head 20 will be described with reference to FIGS. FIG. 2 shows a state where the cover plate 32 of the camera head 20 is opened upward. In FIGS.
Reference numeral denotes a supply box housed on the left side of the camera head 20, in which an unphotographed film 36 is housed. FIG. 2 also shows the cover plate 38 of the supply box 34 opened upward. In the supply box 34, the remaining amount of the film 36 wound on a supply reel (not shown) is monitored by a swing lever 40.

An aperture mask 44 is detachably mounted on the lower frame 42 of the camera head 20 from the front. A frame window 46 is formed in the mask 44 as shown in FIG.
The mask 44 is fixed at a position on the optical axis. The mask 44 is provided with a light shielding plate 48 for judging the type of the mask. When the mask 44 is set on the frame 42, the camera head 20 automatically determines the type of the mask 44 from the position of the light shielding plate 48.

Reference numeral 50 denotes a guide roller, and reference numeral 52 denotes a drive roller, which are disposed on the left and right sides of the mask 44. The film 36 supplied from the supply box 34 is guided by the light shielding roller 54 provided in the supply box 34 and the guide roller 50 to reach the upper surface of the mask 44. Then, it is sandwiched between the drive roller 52 and the contact roller 56, and is wound on a winding-side reel (not shown) while being given a predetermined tension by a tension roller 58. The take-up reel is loaded while being accommodated in a magazine (not shown), and engages with the take-up shaft 60 to rotate.

Reference numeral 62 denotes a pressure plate. FIG.
The upper plate 64 is overlapped as shown in FIG. A concave portion 68 is formed on the upper surface of the pressure plate 62 for forming an air chamber between the pressure plate 62 and the upper plate 64.
A plurality of small holes 70 communicating with the lower surface of the pressure plate 62 are open at 8.

At the center of the upper plate 64, a pipe 72 stands upright.
A coil spring 76 is compressed between a flange 74 fixed to the pipe 72 and the upper plate 64. A rubber tube 78 is connected to the pipe 72 (see FIGS. 2 and 3), and the other end of the tube 78 is connected to a diaphragm type air pump (not shown). The pipe 72 communicates with the recess 68 of the pressure plate 62.

The pressure plate 62 is driven up and down by an electromagnetic actuator 82 via an L-shaped bracket 80. That is, as shown in FIG. 4, the lower portion 80a of the bracket 80 is clamped between the washer 74 fixed to the pipe 72 and the coil spring 76, while the vertical portion 80b of the bracket 80 is provided with two screws on the frame 42. It is held movably up and down by 84 and 86.

The electromagnetic actuator 82 includes the plunger 8
2a and an electromagnetic coil 82b (FIG. 3), and the lower end of the plunger 82a is attached to the upper end of the vertical portion 80b by a pressure release lever 88. Both ends of a tension coil spring 90 are locked to the lever 88 and the lower screw 86.

For this reason, the plunger 82a and the bracket 80 are given a downward return behavior by the coil spring 90, and the pressing plate 62 is pulled by the tensile force of the spring 90.
Is pressed by the mask 44 via the coil spring 76. Accordingly, at the time of photographing, the film 36 placed on the mask 44 is positioned between the mask 44 and the pressure plate 62 and positioned.

At this time, the inside of the concave portion 68 is sucked to a negative pressure through the tube 78 and the pipe 72 by the plunger pump, and the film 36 is sucked from the small hole 70 to the lower surface of the pressure plate 62. For this reason, the film 36 adheres to the lower surface of the pressure plate 62 without loosening in the frame window 46 of the mask 44, and the planar accuracy of the film 36 at the time of photographing is improved.

When the film 36 is moved, the electromagnetic solenoid 82b of the electromagnetic actuator 82 is excited, and the pressure plate 62 is sucked upward together with the plunger 82a. As a result, the pressure plate 62 separates from the film 36, and the film 36 becomes movable. In this state, the drive roller 52 rotates by a predetermined angle, feeds the film 36 by one frame, and puts an unphotographed area of the film 36 into the frame window 46.

Next, the contact roller 56 will be described with reference to FIGS. FIG. 5 is an exploded view showing a cross section of the contact roller 56 together with the drive roller 52, and FIG. 6 is a view showing a surface shape of the contact roller 56. The drive roller 52 has an annular groove 100 having substantially the same width as the film 36 on the outer peripheral surface. The contact roller 56 has substantially the same width as the annular groove 100, and rolls while pressing the film 36 against the annular groove 100.

The contact roller 56 is made of aluminum and has a substantially thin cylindrical shape, and is held on a support shaft 104 by two roller bearings 102, 102. That is, the two roller bearings 102, 102 are fixed to a support shaft 104 with a spacer 106 interposed therebetween.
And a nut 110.

The outer peripheral surface 112 of the contact roller 56
As shown in FIG. 6, a central portion 112a formed of a cylindrical surface,
Both ends 112b smoothly connected to the center 112a
(Only one is shown in FIG. 6). The two ends 112b are formed such that the angle α formed by the tangent B on the plane including the rotation axis A with the rotation axis A and the angle α = 0 formed by the tangent C (parallel to the rotation axis A) at the center 112a with the rotation axis A
And a curved surface that increases continuously and smoothly.

For example, the curved surfaces of both ends 112b can be formed as follows. That is, on a plane including the rotation axis A, a curved surface obtained when an arc of radius R having a center E on a straight line D passing through the edge of the central portion 112a and orthogonal to the rotation axis A and having a center E is rotated around the rotation axis A. can do. Instead of the circular arc having the radius R, a curved surface obtained by rotating a curve of another shape such as an elliptic curve or a quadratic curve around the rotation axis A may be used.

It is desirable that the surface (film contact surface) of the contact roller 56 be chrome-plated. At this time, since the surface of the contact roller 56 has no edge, burrs due to plating do not occur on the surface. In addition, it is preferable to perform a dent treatment (a plating treatment name of Yoshizaki Plating Co., Ltd.) when applying the chrome plating, because the plating surface color can be made black.

In the above embodiment, the contact roller 56 is made of aluminum. However, a hollow stainless steel may be used instead of aluminum, or a synthetic resin plated with conductive material may be used. Also, this contact roller 56
Is applied to the light blocking roller and the tension roller 58,
It is desirable to reduce these moments of inertia and rotational frictional resistance. In this case, slippage between the rollers 54 and 58 and the film 36 due to intermittent running of the film 36 can be reduced, and scratches generated on the film 36 due to the slippage can be reduced.

[0033]

According to the first aspect of the present invention, both ends (112b) of the outer peripheral surface of the contact roller (56) are
Since the angle (α) formed by the tangent line (B) with the rotation axis (A) is formed by a curved surface that increases continuously from the central portion (112a), the contact roller (56) is formed on the film (36). Is less likely to form an indentation on the film (36) when it comes into contact with the film.

Further, since the contact roller (56) is made of a hollow cylinder, it is light in weight and has a small moment of inertia. For this reason, when the film (36) is intermittently fed, slip generated on the surface of the film (36) is reduced, and the slip on the film (36) is reduced.

If the contact roller (56) is made of a hollow aluminum cylinder and chrome-plated on its surface and is supported by roller bearings, the rotation is further smoothed and the rotation on the film (36) surface is improved. Scratch damage can be further reduced (claim 2). The light-shielding roller (54) and the tension roller (58) are also formed of a hollow cylinder like the contact roller (56), and if the moment of inertia is reduced, the sliding of these rollers is reduced, and the damage to the film (36) is reduced. It is possible to further reduce.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of a flat-bed micro camera.

FIG. 2 is a front view showing the internal structure of the camera head.

FIG. 3 is an enlarged perspective view near a mask.

FIG. 4 is an exploded perspective view showing the vicinity of a pressure plate.

FIG. 5 is a diagram showing a cross section of a contact roller and a drive roller.

FIG. 6 is a diagram showing a surface shape of a contact roller.

FIG. 7 is a diagram showing a cross section of a conventional contact roller and a drive roller.

[Explanation of symbols]

 Reference Signs List 18 shooting lens 36 film 44 aperture mask 46 frame window 52 drive roller 56 contact roller 62 pressure plate 100 annular groove 102 roller bearing 112 contact roller outer peripheral surface 112a central portion 112b both ends A rotation axis B, C tangent α angle

Claims (2)

(57) [Claims] 1. A flat-bed type in which a film is sandwiched between an aperture mask and a pressure plate perpendicular to an optical axis of a photographing lens, and a reduced image of a subject by the photographing lens is projected onto the film through a frame window formed in the aperture mask. In the micro camera, a drive roller formed with an annular groove for engaging the film and positioning the film in the width direction, and a contact formed of a hollow cylinder and engaged in the annular groove to press the film against the drive roller An outer peripheral surface of the contact roller, a center portion formed of a cylindrical surface, and both end portions formed of curved surfaces that are continuous with the center portion and whose tangents and the rotation axis form an angle that continuously increases from the center portion. A flat-bed type micro camera characterized by being formed by: 2. The flat-bed type micro camera according to claim 1, wherein the contact roller is formed of a hollow cylinder made of aluminum having a chrome plating on a surface, and is supported on a support shaft by a roller bearing.