JPS6333207Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lens exchange device designed to enable quick lens exchange even in a narrow space, and to position the lens with high precision and set it in the main body of an optical device.

A microfilm reader printer can be mentioned as one of various optical devices. The first diagram showing the schematic structure of this microfilm reader printer
As shown in the figure, a microfilm 2 is sandwiched between a film carrier 1 formed of a pair of glass plates.
is illuminated with illumination light from the lamp chamber 3. For this reason, the image recorded on the microfilm 2 is magnified by the lens 4 and then reflected by the reflecting mirrors 5, 6, and 7 to form an image on the screen 8. On the other hand, a plurality of conveyor belts 9 convey photosensitive paper (not shown) in a direction perpendicular to the plane of the drawing. A charging device, a developing device, and a fixing device (not shown) are arranged in this order along the conveying direction of the conveying belt 9 to constitute an electrophotographic copying apparatus. Therefore, when the reflecting mirror 6 is rotated to the position shown by the two-dot chain line in the figure, the image on the microfilm 2 is magnified by the lens 4, then reflected by the reflecting mirrors 5 and 10, and is incident on the photosensitive paper side. I'm starting to do that. Thus, a print is produced by copying the image using the electrophotographic copying device. Note that the reference numeral 11 in the figure is the main body case.

In this manner, the microfilm reader printer allows images to be observed on the screen 8 and also allows prints of images recorded on the microfilm 2 to be created using the electrophotographic copying device.

In such a microfilm reader printer, it may be necessary to change the magnification of the image on the microfilm 2. Therefore, the lens 4 can be selectively replaced as appropriate.

FIG. 2 is a plan view showing this part according to the prior art, that is, the main part of a lens changing device capable of selectively changing the lens 4. As shown in the figure, the lens barrel holder 13 is made of a rectangular member, and has a plurality of (two in this example) lens barrels 4a, each having a different focal length.
4b are disposed and fitted in the longitudinal direction, and can rotate within a horizontal plane with the support shaft 14 as the rotation center. At this time, the distance from the center 14a of the support shaft 14 to the center of the first lens barrel 4a, that is, the optical axis 4c, and the distance from the center 14a of the support shaft 14 to the center of the second lens barrel 4b, that is, the optical axis 4d. is set equal to . Now, if the first lens barrel 4a is used, its optical axis 4c coincides with the optical axis 12a of the condenser lens 12. To replace the lens barrel 4b with the second lens barrel 4b from this state, rotate the lens barrel holder 13 and align the optical axis 4d of the second lens barrel 4b with the condenser lens 1.
The optical axis 12a of No. 2 may be aligned with the optical axis 12a of No. 2.

However, in such a conventional lens exchange device, the lens barrels 4a and 4b are selectively exchanged by rotating the lens barrel holder 13 about the support shaft 14.
A large horizontal area is required to allow rotation of the lens barrel holder 13, and the length, shape, mounting position, etc. of other parts are restricted.

SUMMARY OF THE INVENTION In view of the prior art described above, an object of the present invention is to provide an optical lens exchange device that can easily selectively exchange lens barrels with a small footprint.

The lens changing device of the present invention that achieves the above object includes a lens turret rotatably fitted to a turret holder, and a lens turret formed on the lens turret at an equal distance from the center of rotation of the lens turret. A plurality of lens barrel mounting holes into which lens barrels are removably inserted, a slider rotatably holding a focusing ring screwed into the turret holder, and a lens provided between the slider and the turret holder. a means for preventing rotation of the turret holder against rotational operation of the focusing ring; and a means for holding the slider so as to be slidable in a direction intersecting the optical axis of a lens fixed to the main body of the optical device and incorporated in the lens barrel. a slider guide, a stopper formed on the slider guide to restrict the pushing end of the slider with respect to the slider guide, and a positioning member screwed into the slider guide parallel to the turret holder and having a tapered seat surface. a bolt, a groove carved into the slider so as to face the stopper portion and into which the shaft of the positioning bolt is inserted; and a groove formed integrally with the groove on the slider and corresponding to the tapered bearing surface of the positioning bolt. A positioning surface having a shape, and a bolt operation knob that is integrally formed with the head of the positioning bolt and that can fix the slider located at the push-in end to the slider guide.

Hereinafter, an embodiment in which the present invention is applied to a microfilm reader printer will be described in detail with reference to the drawings.

Figure 3a is a sectional view of this embodiment seen from the front side with respect to Figure 1, Figure 3b is its plan view, and Figure 3c.
FIG. 2 is an exploded perspective view of the main parts of this embodiment. As shown in these figures, a disc-shaped lens turret 1
5a is inserted into a ring-shaped turret holder 15c which supports this lens turret 15a so that it can freely rotate about its center 15b. Therefore, the lens turret 15a can be pulled out from the turret holder 15c by pulling it upward in FIG. 3c. A plurality of (two in this example) lens barrels 4a and 4b, each having a different focal length, are mounted on the lens turret 15a so that their optical axes 4c and 4d are equidistant from the center 15b of the lens turret 15a. It is detachably fitted into the formed lens barrel device hole 15m. Thus, by rotating the lens turret 15a, the lens barrels 4a, 4b can be rotated in a horizontal plane about the center 15b of the lens turret 15a. Furthermore, the positioning pin 15f protrudes upward from the turret holder 15c and is attached to the lower surface of the lens turret 15a.
It can be fitted into a pair of pin holes 15n carved 180 degrees apart, and when the positioning pin 15f is fitted into the pin hole 15n in this way, the lens barrels 4a and 4b are positioned at predetermined positions. I'm starting to do that.

The slider guide 16 has a frame shape that is bent into a thin shape, and its upper end surface 16a is connected to the main body housing 1.
1, and a window 16c is formed on its side surface 16b. The bottom surface of the slider guide 16 is a sliding guide portion 16d, and a stopper portion 16e is provided at the end of the sliding guide portion 16d. The slider 17 slides along the sliding guide portion 16d of the slider guide 16 and is held by the slider guide 16. Further, the slider 16 is formed with a groove 17c having a conical positioning surface 16a and a pair of notches 17d. Furthermore, lens barrels 4a and 4b housing lenses (not shown) are removably loaded into the slider 17 via a lens turret 15a and a turret holder 15c.

Describing the loading structure of the lens barrels 4a and 4b in detail, the focusing ring 18 is fitted to the slider 17 so that it can freely move up and down and rotate. Turret holder 15c holding lens turret 15a
is screwed inside the focusing ring 18, and the slider 17
It is provided with a detent 15e that engages with a detent pin 17e screwed onto the detent 15e. On the other hand, on the inside of the lower part of the focusing ring 18 is a floating mask 19 that engages with the protrusion 17f of the slider 17 and is prevented from rotating.
are screwed together. Therefore, when the focusing ring 18 is rotated, the lens barrels 4a and 4b are aligned with the turret holder 15c and the lens turret with reference to the position where the lower surface of the floating mask 19 contacts the upper surface of the film carrier 1 (see FIG. 1). Focusing can be performed by moving together with the lens 15a in a direction parallel to the optical axis of the lens. Note that the rotation prevention structure is not limited to the one shown in the drawings, and any structure may be used as long as it restricts the rotation of the turret holder 15c and floating mask 19. Also, the focusing ring 18 is connected to the slider 1.
A steel ball 24 is placed between these so that the steel ball 24 moves smoothly within the
is interposed.

A nut 20 is fixed to the sliding guide portion 16d of the slider guide 16. This nut 20
is positioned so as to face the positioning surface 17a via the groove 17c when the slider 17 is inserted into the slider guide 16 and abuts against the stopper portion 16e. Note that the groove portion 17c having the positioning surface 17a formed at the upper end thereof is open to the tip surface 17b of the slider 17. Further, the positioning bolt 21 has a tapered seat surface 21a formed in a shape corresponding to the positioning surface 17a so that the shaft portion 21b thereof passes through the groove portion 17c and tightly engages with the positioning surface 17a. A disk-shaped operation knob 22 is fixed to the head. A portion of this operating knob 22 protrudes to the outside of the side surface 16b through the window 16c.

The operation of this embodiment having such a configuration will be explained.

First, I will explain the installation procedure. Desired lens barrels 4a, 4b
The side surface 16 is attached to the notch 17d of the slider 17 on which the slider 17 is attached.
The slider 17 is inserted into the slider guide 16 by fitting and guiding the slider 17 along the sliding guide portion 16d. When this happens, the shaft portion 21b of the positioning bolt 21 passes through the groove portion 17c, and the tip end surface 17b abuts against the stopper portion 16e. In this state, when the operating knob 22 is turned and the positioning bolt 21 is screwed into the nut 20, the tapered seat surface 21a comes into sliding contact with the positioning surface 17a of the groove 17c, so the slider 17 is pressed toward the stopper portion 16e by component force. Ru. As a result, the tip surface 1
7b is in close contact with the stopper portion 16e, and the slider 1
The position of 7 in the insertion direction and the position in the lateral direction perpendicular to the insertion direction are determined to be precisely constant positions. At this time, one lens barrel 4a is positioned at a predetermined position above the lamp chamber 3 (see FIG. 1), and the optical axis of the lens 4a automatically aligns with the main body side.

Next, when pulling out the slider 17, make sure that the operating knob 2 is in the position as described above.
2 in the opposite direction, and the positioning bolt 21 is attached to the nut 2.
Rotate it from 0 until it loosens. Positioning bolt 2
When slider 1 loosens and moves upward, slider 1
7 from the slider guide 16.

On the other hand, when changing the magnification by only rotating the lens turret 15a, that is, FIGS. 3a and 3b show a case where one lens barrel 4a is used, but from this state, it is necessary to change to the other lens barrel 4b. In this case, it is sufficient to lift the lens turret 15a slightly upward and rotate it while releasing the engagement with the positioning pin 15f. When the lens turret 15a is rotated by 180 degrees, the positioning pin 15f is inserted into the other pin hole 15n of the lens turret 15a.
If the lens 4b is inserted, the optical axis 4d of the lens 4b is positioned at a predetermined position.

FIG. 4 is a sectional view from the left side showing another embodiment in which the positioning mechanism of the lens turret 15a is different. As shown in the figure, the lens turret 1
A positioning member 15g having a click 15h projecting upward from the end of the ring-shaped member on the lower surface of the member 5a.
are fixed by bolts 15i and 15j.
A spring 23 is interposed between the bolt 15j and the lower surface of the positioning member 15g, so that the positioning member 15g
It is designed to be able to bend against the spring force of the spring 23 using i as a fulcrum. On the other hand, at two positions 180 degrees apart on the lower surface of the turret holder 15c, there are recesses 15k and 15l into which the clicks 15h can fit.
is formed. Therefore, lens turret 1
When rotational force is applied to the lens turret 15a, the engagement between the click 15h and the recess 15k is released, and when the lens is rotated 180 degrees, the click 15h is fitted into the recess 15l.
b can be placed in a predetermined position.

As described above in detail along with the embodiments, according to the present invention, lenses can be easily selected and replaced simply by rotating the lens turret.
At this time, since the lens turret only rotates within the same horizontal plane about its center, the occupied area does not increase due to this rotation.
In addition, a rider that supports a plurality of lens barrels is inserted into the slider guide, and the tip surface of the slider is in close contact with the stopper portion of the slider guide.
Since the positioning surface formed on the slider has a tapered seat surface and engages with the positioning bolt, it is possible to accurately replace the lens barrel arranged in a narrow space with a simple and inexpensive structure.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a microfilm reader printer, FIG. 2 is a plan view showing an optical lens holder according to the prior art, FIG. Figure b is the plan view,
FIG. 3c is an exploded perspective view thereof, and FIG. 4 is a sectional view showing another embodiment of the present invention as seen from the left side. In the drawing, 4a and 4b are lens barrels, 11 is a main body housing,
15a is the lens turret, 15b is the center, 15
c is a turret holder, 15e is a rotation stopper, 15
m is the lens barrel mounting hole, 16 is the slider guide, 16d
17 is a sliding guide, 17 is a slider, 17a is a positioning surface, 17c is a groove, 17d is a notch, 17e is a stopper pin, 18 is a focusing ring, 20 is a nut, 21 is a positioning bolt, 21a is a tapered seat surface, 21b 2 is a shaft portion, and 22 is an operation knob.

Claims (1)

[Scope of utility model registration request] A lens turret rotatably fitted to a turret holder, and a plurality of lens barrels formed on the lens turret at equal distances from the rotation center of the lens turret, into which lens barrels are removably inserted. a mounting hole, a slider that rotatably holds a focusing ring that is screwed into the turret holder, and a slider that is provided between the slider and the turret holder to allow the turret holder to rotate the focusing ring. a slider guide that is fixed to the optical device main body and holds the slider slidably in a direction intersecting the optical axis of the lens incorporated in the lens barrel; a stopper portion that restricts the pushing end of the slider relative to the slider guide; a positioning bolt that is screwed into the slider guide in parallel with the turret holder and has a tapered seat surface; a groove into which the shaft of the positioning bolt enters; a positioning surface formed integrally with the groove on the slider and having a shape corresponding to a tapered seat surface of the positioning bolt; and a head of the positioning bolt. and a bolt operating knob integrally formed with the slider guide and capable of fixing the slider located at the push-in end to the slider guide.