JPH01280739A - Shutter for camera - Google Patents

Abstract

PURPOSE:To simplify a stage and to abate cost by integrally forming shafts journaling a charge lever and a driving lever which place big strength on a shutter plate by means of a synthetic resin and thickening the board thickness of the periphery of the shafts in the way that the thickness is thicker than the board thickness of the other part. CONSTITUTION:Shafts 40, 41 and 42 for supporting driving levers 60 and 61 which drive the group of shutter blades in the way that the driving levers are capable of rocking are integrally formed by means of the shutter plate and the synthetic resin. Then, the wall thickness of the periphery of the shafts on a side surface on which the axes 40, 41 and 42 project is thickened in the way that the thickness is thickener than the wall thickness of the periphery of an aperture 20a and the shafts are integrally formed. Thus, the plate which is high in rigidity and is never distorted due to big strength placed on the shafts 41 and 42 is obtained. Then, even if the peripheral area 49 of the aperture 20a of the plate has wall thickness identical to the wall thickness of an ordinary metal plate, a plate which is high in rigidity is available and the size of a shutter part occupying in a camera is not increased. Thus, the stage is simplified, and the cost is abated.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a camera shutter.

[Conventional technology]

FIG. 3 shows a focal plane shutter as a conventional camera shutter.

In the figure, 1 is a shutter base plate, 2 is a blade drive lever shaft, and a main arm rotation shaft 2a is formed at one end. 3 is a charge lever shaft 3.4 is an auxiliary arm rotation axis, which is the center of rotation of a charge lever (not shown) for charging the blade drive lever 2; 5.6 is a shaft for attaching the cover plate 16 to the shutter base plate 1; , 7 is an aperture formed in the shutter base plate 1, and 8 is an axis of each of the above-mentioned axes 2. 3
．． 4. , 5. 6 is a hole formed in the shutter base plate 1 for caulking, and 9 is a groove (hole) formed in the shape of the swinging range of the swing shaft (not shown). 10 is a leading blade group, which includes a main arm 10a and an auxiliary arm 10b.
The slit forming blade 10c and the other divided blade 10d are linked and supported by the caulked portion 10e. In addition,
The main arm 10a is swingably supported by the main arm rotation shaft 2a of the blade drive lever shaft 2, and the auxiliary arm 10b is swingably supported by the auxiliary arm rotation shaft 4. 11
is the rear blade group, the main arm lla and the auxiliary arm Il
In b, the slit forming blade 11c and another divided blade lid are linked and supported by the caulking portion 11e. In addition,
The main arm lla is swingably supported by the main arm rotation shaft 2a, and the auxiliary arm llb is swingably supported by the auxiliary arm rotation shaft 4. 12 is a partition plate arranged between the leading blade group 10 and the trailing blade group 11 to prevent interference between the two. Note that the partition plate 12 is also formed with an opening 12a corresponding to the aperture described above. A cover plate 3 is made of a thin metal plate like the shutter base plate 1, and has an opening 3a corresponding to the aperture. 14. 15 is a spacer, and each blade group 10. In order to keep the blades 11 running smoothly, the tip regions of the blades 10c, 10d, llc, and lid are arranged at sliding positions.

[Problems to be Solved by the Invention] In this conventional shutter structure, the blade drive lever shaft 2, the charge lever shaft 3, the auxiliary arm rotation shaft 4, and the shafts 5 and 6 are crimped into the holes 8 in the shutter base plate L. Since the shutter base plate unit was installed using the same method, it took time to complete the shutter base plate unit, and the cost was also high.

Therefore, in order to reduce costs and simplify the process, it is conceivable to mold the shutter base plate from a synthetic resin and integrally mold the various shafts mentioned above at the same time. However, since the shutter base plate is a thin member, if a large force is applied to the blade drive lever, charge lever, etc. with a molded product made of synthetic resin, the force will cause deformation, which will have a subtle effect on the movement of each blade group. It is expected that it will be given. In this case, the accuracy of the shutter exposure (in seconds) cannot be guaranteed, and in the worst case, it is expected that the shutter base plate will be damaged due to insufficient strength.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a camera shutter having a shutter base plate that does not cause problems in terms of strength even if it is made of synthetic resin by molding.

[Means for solving problems]

The present invention features a shutter base plate molded from synthetic resin, in which the shaft that supports the charge lever and drive lever, which is easily deformed due to the greatest force and affects the charge stroke, etc., is integrally molded, and the surrounding parts of the shaft are formed integrally. It features a camera shutter that is thicker than other parts (molded), is inexpensive, and greatly simplifies the assembly process.

〔Example〕 Embodiments of the present invention are shown in FIGS. 1 and 2. FIG.

20 is a shutter base plate molded from liquid crystal polymer (LCP) as a synthetic resin material, 23 is a main arm rotation axis, 24 is an auxiliary arm rotation axis, 25. 26 is cover plate 1
3 is the mounting shaft, 27 is a rib, and 30.31 is a thick part, and this rib 27 and thick part 30.31 are connected to both blade groups 10.1.
It is formed on the edge of the shutter base plate 20 within a range that does not impede the movement of the shutter base plate 20, and can improve strength (prevent warpage, prevent breakage, etc.) and improve flatness. Reference numeral 40 denotes an axis that is the center of rotation of a charge lever 50 for charging both the leading blade and trailing blade drive levers 60 and 61, which will be described later, and 41 is an axis that is the center of rotation of the leading blade drive lever 60 that drives the leading blade group 10. , 42 is a shaft that is the rotation center of the trailing blade drive lever 61 that drives the trailing blade group 11, and 43 is a light-driven tensioning lever 62 that prevents the leading blade driving lever 60 from being activated.
44 is the rotation center axis of the rear drive tensioning lever 63 that prevents the activation of the rear blade drive lever 61. 45 is a shaft for attaching the base plate 64 for the electromagnet. 43.44. It is fixed at 45.

46. 47. 48 is a thick portion of the shutter base plate 20 that is thicker than the surrounding area 49 of the aperture 20a; 41. 42.43. It is limited around the axis on which the force is applied, such as 44.45. 65 is coil 6
7 is a yoke for generating suction force; 66 is a yoke for generating suction force by a coil 68;
5.66 is fixed to the main plate 64.

69.70 actuates the shaft portions 62b, 63b of the tensioning lever 62.63 by being attracted by the yoke 65.66, and operates the leading blade and trailing blade drive lever 60. 61 is an armature that is pivoted around shafts 64a and 64b of a base plate 64 as the center of rotation.

Here, axes 23.24. , 25.26.4.0.41.
42°43.44.45 and rib 27 and thick part 46.4
7.48 is integrally molded with the shutter base plate 20. That is, the above various axes 23.24.25.26.40.41
．． 42°43, 44. 45 is integrally molded at the same time as the shutter base plate 20, thereby eliminating the crimping process that was conventionally required.

Here, the operation of charging the shutter will be explained. The foot 50c of the charge lever 50 is biased by a charge transmission member of the main body (not shown), and begins to rotate clockwise in FIG. 3. When the charge lever 50 begins to rotate clockwise (in FIG. 2), the legs 50a, 50b of the charge lever 50 engage the leading and trailing blade drive levers 60. 61, the surface drive lever 60.61 starts to rotate counterclockwise in FIG. 2 against the force of a drive spring (not shown).

As the rotation of the surface drive lever 60, 61 progresses, the surface drive lever 60.
The shutters are charged to a position where the tensioning parts 60a, 61a of the tensioning levers 60, 61 are engaged and locked with the tensioning parts 62a, 63a of the tensioning levers 62, 63, respectively, and charging of the shutter is completed.

At this time, since the spring force driving the surface drive lever 60.61 is very large, the shaft 40.41 is
．． A very large force is applied to 42.

At this time, if the rigidity of the shutter base plate 20 is weak, the shutter base plate 20 will be deformed (warp, etc.) and the shaft will sag, causing the chassis strobe to extend.
Accidents may occur where energy is lost or the battery is not fully charged.

Further, after charging is completed, the surface drive lever 60.61 is moved to the tension lever 62. 63, but the shafts 41°42,
43 and 44 are subjected to a large force due to the drive spring force, if the base plate is deformed (warp, etc.), both blade groups 10. ],
Accidents may occur in which the starting position of 1 is shifted or the timing at which the tension is released is shifted, resulting in a very poor accuracy.

However, according to this embodiment, the thickened portion 4.6 of the main plate 20
．． 47 and 48 to increase the wall thickness around the axis on which force is applied, and also increase the thickness of the shutter base plate 20 on the blade group device side (FIG. 1) to the extent that it does not impede the movement of the blade group. By providing 31, the above-mentioned axis, especially axis 4
It is possible to provide an extremely rigid shutter base plate 20 that does not undergo deformation due to the force applied to the shutter base plate 20. At this time, on the surface of the shutter base plate 20 on the drive lever side (FIG. 2 side), the surrounding area 49 of the aperture 20a can provide a highly rigid shutter base plate 20 even if the thickness is approximately the same as that of the conventional metal base plate, and the camera The size of the shutter portion that closes inside also hardly increases. Further, the overall flatness of the shutter base plate 20 is ensured by ribs 27 provided on the side surfaces of the blade group (FIG. 1). At this time, since the rib 27 is formed between the shutter base plate 20 and the cover plate 13, even if the height is set to the position of the cover plate 13, the volume occupied in the camera does not increase at all.

In the above-described embodiment, the area of the thickened portion 46 is the area of the charge lever 50. The other thickened portion 47.
48, so that the height of one end region of the shutter base plate 20, where various levers and electromagnets are arranged, does not become higher than necessary.

Also, the shaft 40. 41. 42 is further reinforced by providing further circular thickened portions 40a, 41a, and 42a at its base. Here, the shaft 41 has a thickened part 46 which is set slightly lower than the other thickened parts 47 and 48.
2, the circular thickened portion 41, a is set higher than the others to balance the strength with the other shafts 40.

〔Effect of the invention〕

As explained above, by increasing the wall thickness of the shutter base plate only around the axis on which force is applied on the drive side, and by integrally molding the axis, which was conventionally attached by caulking, from synthetic resin, the process has been greatly simplified. In addition to being shortened to
To provide a shutter base plate with sufficiently high rigidity and significantly low cost.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a shutter embodying the present invention, seen from the blade group side. FIG. 2 is a perspective view of a shutter embodying the present invention, seen from the drive lever side. FIG. 3 is a perspective view of a conventional shutter seen from the blade group side.

Claims (5)

[Claims] (1) In a camera shutter that swingably supports a drive lever for driving a group of shutter blades and has a shutter base plate molded from synthetic resin, a shaft for swingably supporting the drive lever is provided. A shutter for a camera, characterized in that it is integrally molded with the shutter base plate, and the wall thickness around the shaft on the side where the shaft protrudes is made thicker than the wall thickness around the aperture. (2) In a camera shutter that swingably supports a charge lever for charging a drive lever that drives a group of shutter blades, and has a shutter base plate molded from synthetic resin, the charge lever is swingably supported. The shutter base plate is characterized in that a shaft is integrally molded with the shutter base plate, and the wall thickness around the shaft on the side where the shaft protrudes is thicker than the wall thickness around the aperture. Shutter for camera. (3) In a camera shutter having a shutter base plate molded from synthetic resin, the camera shutter swingably supports a leading blade driving lever and a trailing blade driving lever for driving a shutter leading blade group and a trailing shutter blade group, and has a shutter base plate molded from synthetic resin. A first shaft for swingably supporting the leading blade drive lever and a second shaft for swingably supporting the trailing blade drive lever are integrally molded near one side edge of the shutter base plate. In addition, a shutter for a camera is characterized in that the wall thickness of the surface on the side where the shaft of the side end region projects and the surface on the opposite side are thicker than the wall thickness around the aperture and are integrally molded. (4) A claim in which the shaft is integrally formed near one side edge of the shutter base plate, and a rib is formed protruding from the opposite side of the surface on which the shaft is formed. The camera shutter described in item 2. (5) The camera shutter according to claim 3, further comprising a rib protruding from the other side surface of the surface opposite to the surface on which the first and second shafts are formed.