JPH0678951U - Mounting device for supporting frame of reflecting mirror in overhead projector - Google Patents

Abstract

(57) [Abstract] [Purpose] Since the zoom projection lens and the reflection mirror also move the support frame of the reflection mirror according to the movement of the lens barrel during zooming, the lens and the reflection mirror maintain their fixed positions, so the reflection mirror is more than necessary. No need to make it big. A projection 17 having a circular peripheral side surface 17a is provided on the upper surface of a rotary lens barrel 16 in which a lens 18a is housed so as to surround the lens 18a. A circular window 6 is provided on the substrate 7 of the support frame A that supports the reflection mirror 5. The circular window 6 is engaged with the protrusion 17 to rotatably mount the substrate 7 on the rotary lens barrel 16. Then, the annular holding piece 20 whose outer portion is located directly above the substrate 7 is placed on the projecting portion 17 and the rotating lens barrel 1 is mounted.
Screw to 6.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a mounting device for a reflecting mirror support frame in an overhead projector.

[0002]

[Prior art]

 For example, as described in Jpn.

[0003]

[Problems to be solved by the device]

 As seen in the above publication, the conventional example is fixedly mounted on the head body side, so when adjusting the focal length of the lens, if the lens barrel is moved vertically while rotating, it will reflect itself. Since the reflection position by the plate is different, it is necessary to use a reflector plate that is large enough to be applied to the vertical movement range of the lens barrel, and depending on the optical system, a reflector plate that is larger than necessary may be used. Must be used.

The present invention has been made by paying attention to the drawbacks of the conventional example.

[0005]

[Means for Solving the Problems]

 In an overhead projector with a zoom projection lens that is fixed on the platen, the zoom projection lens and the reflection mirror move the support frame of the reflection mirror as the lens barrel moves during zooming. The lens barrel holding the support frame of the reflection mirror is rotatable with respect to the support frame, and the support frame of the reflection mirror is composed of a mechanism that suppresses rotation.

[0006]

【Example】

 FIG. 1 shows an embodiment of a device for mounting a reflection mirror support frame in an overhead projector according to the present invention. FIG. 1 is a partially cutaway front view, FIG. 2 is a sectional view of an essential part, and FIG. 3 is a part of FIG. FIG. 4 is a partially cutaway front view showing the relationship between the lens barrel and the head main body, and FIG. 5 is a side view of the overhead projector.

In the figure, A is a reflecting mirror support frame, and the support frame A is constructed by assembling the first constituent frame 1 and the second constituent frame 2 so as to be mutually foldable. , A central piece 3 and side pieces 4 and 4 which are provided by bending opposite ends of the central piece 3, and a reflection mirror 5 is provided on one surface of the central piece 3 and 4 and 4 are assembled to the second component frame 2.

The second component frame 2 is provided with a substrate 7 formed of an annular plate body having a circular window 6 provided in the center thereof, and an engaging piece 8 is provided along the edge of the window 6 of the substrate 7. The left and right ends and the rear end of the substrate 7 are bent to form side rising parts 9 and 9 and a rear rising part 10. Then, the pin 13 provided at one end of the support piece 12 is slidably fitted into the horizontally elongated hole 11 provided in the side rising piece 9, and the other end of the support piece 12 is attached to the side piece of the first configuration frame 1. 4, while the rear end of the side piece 4 is rotatably attached to the side rising piece 9 of the second component frame 2 by the support shaft 14 to form the reflection mirror support frame A. To do.

In the figure, reference numeral 16 denotes a rotating lens barrel formed by screwing a holding barrel 16b into a supporting barrel 16a, and an annular operation piece 16c is provided at the upper end of the supporting barrel 16a of the rotating lens barrel 16. A projecting portion 17 having a circular peripheral side surface 17a which is mounted and engaged is formed so as to surround a projection lens 18a housed in the rotating lens barrel 16, and the projection portion 18c is formed on the upper surface of the operation portion piece 16c. A planar annular guide groove 19 is provided adjacent to the peripheral side surface 17a, and the circular window 6 is projected so that the engaging portion 8 provided on the support frame A is engaged with the guide groove 19. The substrate 7 of the support frame A is placed on the rotating lens barrel 16 by engaging with the portion 17, and the annular holding piece 20 is placed on the projecting portion 17 so that the outer portion is located directly above the substrate 7. Support the tip of the screw 21 through the annular holding piece 20 and the operating portion piece 16c. 16a are screwed into each other to assemble them.

That is, as a result of the reflection mirror support frame A having the reflection mirror 5 and the rotating lens barrel 16 being assembled by the above configuration, they can freely rotate with respect to each other.

A guide pin 22 is projectingly provided on a lower peripheral side of a holding cylinder 16b constituting the rotating lens cylinder 16, and the guide pin 22 is arranged on a peripheral side of a vertical movement lens cylinder 23 accommodating a projection lens 18b. The tilted elongated hole 24a provided therein and the tilted elongated hole 24b provided in the guide cylinder 26 provided in the head main body 25 in a direction opposite to the tilted elongated hole 24a are engaged with each other, so that one of the longitudinal lens barrel 23 A rack 27 is vertically installed on the side, and a pinion 28 that engages with the rack 27 and is driven by a motor 30 is provided on the head main body 25.

Further, a pair of side pieces 29, 29 are provided on the upper end of the head main body 25 via the reflection mirror support frame A and on the rotation locus of the reflection mirror support frame A. It is set up relative.

The head main body 25 provided with the rotary lens barrel 16, the vertical lens barrel 23, and the reflection mirror support frame A provided with the reflection mirror 5 can be folded into a machine base 80 provided with a Fresnel plate. It is supported by a support arm 81 standing upright to constitute an overhead projector B, and the group of projection lenses 18a and 18b of the embodiment constitutes a so-called zoom lens device.

When the switch is operated to drive the motor 30, however, the vertical movement lens barrel 23 is caused by the engagement relationship between the pinion 28 and the rack 27 and the engagement relationship between the inclined elongated holes 24a and 24b and the guide pin 22. Is kept as it is, and the rotary lens barrel 16 moves vertically to a proper position while rotating, and these are mounted on the support barrel 16a of the rotary lens barrel 16 during the vertical movement. Since the support frame A is assembled to the support cylinder 16a in a free state, it does not rotate but moves vertically with the support cylinder 16a, that is, the rotating lens cylinder 16 while maintaining a predetermined position. .

[0015]

EFFECTS OF THE INVENTION Since the present invention is as described above, the reflection mirror always maintains a fixed position with respect to the lens housed in the rotary lens barrel, and therefore absorbs the relative displacement with the rotary lens barrel. Therefore, it is not necessary to make the reflection mirror larger than necessary.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view.

FIG. 2 is a sectional view of a main part.

3 is a partially cutaway enlarged side view of FIG.

FIG. 4 is a partially cutaway front view showing a relationship between a lens barrel and a head portion main body.

FIG. 5 is a side view of the overhead projector.

[Explanation of symbols]

 A Reflection mirror support frame 5 Reflection mirror 6 Circular window 7 Substrate 16 Rotating lens barrel 17 Projection portion 20 Annular holding piece 21 Screw

Claims (1)

[Scope of utility model registration request] 1. In an overhead projector with a zoom projection lens fixed to a document table, the zoom projection lens and the reflection mirror move together with a mechanism for moving the support frame of the reflection mirror in accordance with the movement of the lens barrel during zooming. In this case, a device for mounting the reflection mirror, comprising a lens barrel that holds the support frame for the reflection mirror, which is rotatable with respect to the support frame, and the support frame for the reflection mirror has a mechanism that suppresses rotation.