JP2504983Y2 - Thin plate mounting structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a thin plate mounting structure in which a thin plate is mounted on a base and the opening is closed.

[Conventional technology]

As a shutter for opening and closing the passage of incident light to the film loaded in the camera and exposing it for a certain period of time, there is, for example, one shown in FIG. In FIG. 6, reference numerals
Reference numerals 101 and 102 denote a pair of shutter blades that open and close the path of an incident light beam that has passed through the taking lens. The pair of shutter blades 101 and 102 are housed in the blade chamber 104 through the opening 103a of the base 103, and a thin plate 105 is attached to the opening 103a of the base 103 by a mounting screw 106.

The mounting screw 106 mounted on the periphery of the opening 103a is
In order to make the entire shutter compact, there is a place where a screw hole 107 is provided on one side (left side in FIG. 6) of the opening 103a, but on the other side (right side in FIG. 6). There may be no place. In such a case, provide a screw hole 107 on only one side, and attach the screw
The thin plate 105 closes the opening 103a by screwing 106 together.

[Problems to be solved by the device]

However, in such a conventional thin plate mounting structure, the thin plate 105 may be slightly warped from the beginning, or may be erroneously plastically deformed at the time of mounting. In such a case, one side (the left side in FIG. 6) of the thin plate 105 is closely attached to the peripheral edge of the opening 103a by the mounting screw 106, but the other side (the right side in FIG. 6) has one point. As shown by the chain line, it floats up from the peripheral edge of the opening 103a.
In this way, if the other side of the thin plate 105 rises,
There is a problem that the gap between the shutter blades 101 and 102 becomes larger than a predetermined gap, and light leaks from this gap toward the film surface.

If the thin plate 105 is pressed by a separate mounting screw in order to prevent the thin plate 105 from floating, there is a problem in that the efficiency of the plane space in the design is reduced and the cost is increased as a whole due to an increase in the number of parts.

[Means for solving the problem]

In order to solve such a problem, in the present invention, a base having a screw hole and a seat surface of the screw on the periphery, and a mounting hole facing the screw hole on the periphery and parallel to the base. In the mounting structure of a thin plate that includes a thin plate supported on the base and a mounting screw that is inserted into the mounting hole and screwed into the screw hole to mount the thin plate to the base, the seat surface is located in the center of the base rather than the screw hole. The portion on the side of the base is formed lower than the portion on the side of the outer edge of the base than the screw hole. Alternatively, a convex portion is formed on a portion of the surface of the thin plate facing the base, which is closer to the outer edge than the mounting hole.

[Action]

According to the first aspect of the present invention, the portion of the seat surface closer to the center of the base than the screw hole is formed lower than the portion closer to the outer edge of the base than the screw hole. Therefore, when a thin plate is attached to the base by screwing a mounting screw into the screw hole, the thin plate contacts the head part of the screw and the seat where it abuts on the seat surface on the outer edge side of the base rather than the screw hole. The thin plate has a gap between it and the seat surface on the center side of the base rather than the screw hole. Therefore, if the mounting screw is further screwed in while the screw head of the mounting screw is in close contact with the thin plate, the portion of the thin plate (the central portion of the thin plate) facing the seat surface portion on the central portion side of the base rather than the screw hole is It is pushed by the screw head of the mounting screw and tilts toward the base. Further, according to the configuration of the second aspect of the present invention, the convex portion is formed in the portion of the surface of the thin plate facing the base, which is closer to the outer edge than the mounting hole. Therefore, when a mounting screw is screwed into the screw hole to mount the thin plate on the base, the portion of the thin plate closer to the center than the mounting hole inclines toward the base more than the portion closer to the outer edge than the mounting hole. Therefore, according to the first and second aspects of the present invention, it is possible to prevent the central portion of the thin plate from floating above the mounting surface at the peripheral edge of the base. Therefore, when the present invention is applied to the shutter, the gap between the plurality of shutter blades housed in the blade chamber in the base does not become larger than the predetermined distance.

〔Example〕

Hereinafter, the present invention will be described with reference to the drawings. 1 to 3 are views showing a first embodiment of the present invention.

In FIGS. 1 and 2, reference numerals 1 and 2 denote a pair of shutter blades for opening and closing the passage of an incident light beam that has passed through the taking lens to perform exposure. The pair of shutter blades 1 and 2 are driven. It is opened / closed via an opening / closing lever 3 operated by a mechanism (not shown). A pair of shutter blades 1, 2
Is accommodated in the blade chamber 5 formed in the synthetic resin base 4 through the opening 4a. Shutter blades on the base 4
Pins 6 and 7 for rotatably supporting the pins 1 and 2 are formed in a protruding manner, and two screw holes 8 are provided on one side (upper side in FIG. 2) of the peripheral edge of the opening 4a. 9 is formed.

A thin metal plate is attached to the mounting surface 4b around the opening 4a of the base 4.
10 is placed, and this thin plate 10 has a shutter opening at its center.
10a is formed, and two insertion holes (mounting holes) 11 and 12 are formed at positions corresponding to the screw holes 8 and 9. Insertion hole 11,
The thin plate 10 is attached to the opening 4 a of the base 4 by inserting two mounting screws 13 and 14 into the 12 and screwing them into the screw holes 11 and 12.

Here, as shown in FIG. 3, the seating surface 4c of the mounting surface 4b of the base 4 closer to the opening than the screw hole 8 (the seating surface portion closer to the center of the base than the screw hole) 4c is The seat surface on the opposite side (the seat surface portion on the outer edge side of the base with respect to the screw hole) 4d is formed to be lower in height in the screw mounting direction. There is a gap between the thin plate 10 and the seat surface portion 4c closer to the center of the base than the screw hole 8. Therefore, when the mounting screw 13 is screwed into the screw hole 8 and the thin plate 10 is mounted on the mounting surface 4b of the base 4, the thin plate 10
Is contacted with the seat surface portion 4d on the outer edge side of the base 4 with respect to the screw hole 8, and is sandwiched between the head of the mounting screw 13 and the seat surface 4d to be in close contact therewith. Due to the gap, the thin plate portion (the central portion of the thin plate 10 in FIG. 1) facing the seat surface portion 4c closer to the central portion of the base than the screw hole 8 is pushed by the screw head of the mounting screw 13. When the base 4 side (opening 4a side, that is, the lower right side in FIG. 1) is tilted and the mounting screw 13 is further screwed in, the central portion of the thin plate 10 is further pushed by this screw head and the opening 4a is opened.
Elastically deforms toward the side.

Therefore, even if the thin plate 10 is warped from the beginning or is plastically deformed by mistake at the time of mounting, since it is elastically deformed toward the opening side, this opening side portion (right side in FIG. 1). It is possible to prevent the side portion) from floating above the mounting surface 4b at the peripheral edge of the opening 4a. Therefore, the gap between the shutter blades 1 and 2 housed in the blade chamber 5 does not become larger than the predetermined gap, and it is possible to prevent light leakage from the gap toward the film surface.

Further, since the thin plate 10 is elastically deformed so as to prevent the thin plate 10 from rising from the peripheral edge of the opening, a separate mounting screw for preventing the floating is not necessary. Therefore, the design space efficiency is improved,
Since the number of parts can be omitted, the cost can be reduced as a whole.

By the way, since the thin plate 10 is elastically deformed by the mounting screws 13 and 14, the space in the blade chamber 5 on the opening side (right side in FIG. 1) is narrowed and the operation of the shutter blades 1 and 2 is hindered. There is a risk. However, since the mounting surface 4b (see the right end in FIG. 1) for mounting the thin plate 10 is formed on the periphery of the opening 4a, the elastic deformation is received by the mounting surface 4b, and the shutter blades 1, 2 The gap is secured within a certain interval, and this operation is not hindered.

FIG. 4 is a diagram showing a second embodiment of the present invention, which is an example applied to a light receiving element mounting portion of an autofocus device for a camera. In the figure, 21 is a housing (base) of a light receiving device that receives light from a light projecting device (not shown) through a light receiving lens 22, and a mounting surface 21a is provided on the right side in FIG. A light receiving window 21b is formed in the center of the light receiving window. A screw hole 23 and a guide pin 24 are provided on the mounting surface 21a, and the printed wiring board 25 faces the mounting surface 21a.
(Thin plate) is located, and guide pins are provided on the printed wiring board.
A long hole 26 for inserting 24 and a long hole-shaped notch (mounting hole) 27 for inserting a mounting screw 29 are formed, and a light receiving element 28 is mounted on the opposite surface of the light receiving window 21b.

The long hole 26 and the notch 27 are formed in the left-right direction in FIG. 4, the guide pin 24 is inserted through the long hole 26, the mounting screw 29 is inserted through the notch 27, and the screw hole 23 is formed. Screw together. here,
The mounting screw 29 is screwed into the screw hole 23 after the printed wiring board 25 is adjusted in the left-right direction so that the relative positions of the light projecting device and the light receiving element 28 have a predetermined relationship.

A projection 30 is provided in a vertically long shape on the seat surface of the screw hole 23 into which the mounting screw 29 is screwed, and on the mounting surface 21a opposite to the light receiving window 21b from the screw hole 23.

That is, the projection 30 (the portion of the seat surface closer to the outer edge of the base than the screw hole) is the seat surface closer to the light receiving window 21b than the screw hole 23 (the seat surface closer to the center of the base than the screw hole). (Part) 21a in the screw mounting direction. For this reason, the mounting screws
When the printed wiring board 25 is attached to the mounting surface 21a of the housing 21 by screwing 29 into the screw hole 23, the printed wiring board 25 is elastically deformed toward the light receiving window 21b side and pressed against the mounting surface 21a. .
Therefore, the relative position of the light receiving lens 22 and the light receiving element 28 is stably fixed, and the distance measuring accuracy is improved.

FIG. 5 is a view showing a third embodiment of the present invention. In this embodiment, the shape of the thin plate is changed, and in FIG.
A projection 42 is formed on the outer edge of the thin plate 41 beyond the insertion hole (mounting hole) 41a and projects toward the seat surface (not shown) of the base. In this embodiment, as shown in FIG. 3, the mounting surface 4b of the base 4 may be provided with a step between the seat surface 4c and the seat surface 4d on the opposite side, but it is not necessary to provide the step. When the mounting plate (not shown) is inserted through the insertion hole (mounting hole) 41a and screwed into the screw hole (not shown) of the base to attach the thin plate to the base, the thin plate is attached due to the convex portion 42. The portion closer to the center than the hole is tilted toward the base side than the portion closer to the outer edge than the mounting hole. When the mounting screw is screwed in, the central portion of the thin plate elastically deforms toward the base side, and the effect is the same as in the first and second embodiments.

In the first and second embodiments, the seat surface portion closer to the central portion of the base than the screw hole is more relative in the screw mounting direction than the seat surface portion closer to the outer edge portion of the base than the screw hole. Although the step is formed in order to lower the height, the present invention is not limited to this, and it may be a slope inclined from the seat surface on the outer edge side of the base to the seat surface on the center side of the base. Further, in the first to third embodiments, the thin plate mounting structure according to the present invention is applied to the camera, but it may be applied to precision equipment other than the camera.

[Effect of device]

As described above, according to the first aspect of the present invention, the seat surface portion closer to the center of the base than the screw hole is formed lower than the seat surface portion closer to the outer edge of the base than the screw hole. Because it is done,
When the mounting screws are screwed into the screw holes, the central part of the thin plate tilts toward the base. Further, according to the configuration of the second aspect of the present invention, the convex portion is formed in the portion of the surface of the thin plate facing the base, which is closer to the outer edge than the mounting hole. Therefore, according to the first and second inventions, when the thin plate is attached to the base by screwing the mounting screws into the screw holes, the portion of the thin plate closer to the center than the mounting hole is closer to the outer edge than the mounting hole. It leans toward the base side compared to the part. Therefore, when the present invention is applied to a shutter, the thin plate is prevented from floating from the peripheral edge of the base. Therefore, the gap between the plurality of shutter blades housed in the blade chamber does not become larger than the predetermined gap, and light leakage from the gap toward the film surface can be prevented. Further, since a separate mounting screw is not required, the efficiency of the plane space in the design is improved and the number of parts can be omitted, so that the cost can be reduced as a whole.

Also, when applied to the light receiving element mounting portion of the autofocus device, the thin plate is pressed against the mounting surface of the base,
The relative position of the light receiving lens and the light receiving element is stably fixed,
Distance measuring accuracy is improved.

[Brief description of drawings]

1 to 3 are views showing a first embodiment in which the present invention is applied to a shutter of a camera, and FIG. 1 is a sectional view of this shutter (a sectional view taken along the line AA in FIG. 2), Fig. 2 is a plan view of this shutter, Fig. 3 is an enlarged perspective view of a portion indicated by an arrow III in Fig. 2, and Fig. 4 is a second diagram in which the present invention is applied to a light receiving element mounting portion of an autofocus device for a camera. FIG. 5 is a perspective view showing an embodiment, and FIG. 5 is a sectional view of a third embodiment of the present invention showing another structure of the thin plate. FIG. 6 is a sectional view showing an example in which a conventional thin plate mounting structure is used for a shutter of a camera. 4,21 …… Base, 4c, 21a …… Seat surface at the center of base, 4d, 30
…… Seat surface on the outer edge of the base, 8,9,23 …… Screw holes, 10,25,41
...... Thin plate, 11,12,27,41a …… Mounting hole, 13,14,29 …… Mounting screw, 42 …… Convex part.

Claims (2)

(57) [Scope of utility model registration request] 1. A base having a screw hole and a seat surface for a screw on the periphery, a thin plate having a mounting hole facing the screw hole on the periphery and supported in parallel with the base, and the mounting hole. In the mounting structure of a thin plate having a mounting screw for inserting the thin plate into the screw hole and mounting the thin plate to the base, the seat surface is closer to the central portion of the base than the screw hole. A mounting structure for a thin plate, wherein a portion is formed lower than the screw hole and a portion on the outer edge side of the base. 2. A base having a screw hole and a seat surface for the screw on the peripheral edge, a thin plate having a mounting hole facing the screw hole on the peripheral edge and supported in parallel with the base, and the mounting hole. In the mounting structure of a thin plate including a mounting screw for inserting the thin plate into the screw hole and mounting the thin plate to the base, from the mounting hole of the surface of the thin plate facing the base. Also, a thin plate mounting structure characterized in that a convex portion is formed on a portion on the outer edge side.