JPS623792Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bounce prevention braking device for rapidly stopping rapidly moving members such as camera shutter members and single-lens reflex camera mirrors without causing them to bounce.

Conventionally, for example, in a braking device for a shutter blade of a camera, one end 2a of a metal plate spring 2 is fixed, and the other free end 2b is fixed, as shown in FIGS. 1a and 1b.
is placed in a position where the protrusion 4a fixed to the shutter blade 4 engages with the leaf spring just before the shutter blade 4 finishes running, and just before the shutter blade 4 finishes running, the protrusion 4a of the shutter blade engages with the leaf spring. 2, the shutter blade 4 was braked by the friction generated when sliding on the surface of the leaf spring 2.

As mentioned above, the metal leaf springs used have a small coefficient of friction, so in order to reliably brake the moving parts, it was necessary to use springs with a large elastic coefficient and strong force. However, using springs with a large elastic coefficient makes it difficult to adjust the force and is prone to permanent deformation. In addition, metal leaf springs make a loud impact noise.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks, to provide an anti-bound braking member that produces low operating noise and stably brakes a running member.

Embodiments of the present invention will be described below with reference to the drawings.

Figures 2 and 3 show an embodiment in which the present invention is applied to a camera shutter device. Figure 2 is an exploded perspective view of the camera shutter device, and Figure 3 is an enlarged view of the bounce prevention braking member. It is a front view. Second
In the figure, an exposure opening 10a is formed in a base plate 10, and two slit grooves 10b, 10c which are parallel to each other in the lateral direction are formed on the sides of the exposure opening 10a. A release locking lever 12 is rotatably provided on the left side of the slit groove 10b, and is biased clockwise by a spring 14.
One end 12a of this lever 12 is formed in the shape of a key, and protrudes near the left end of the slit groove 10b so as to be able to engage a pin 38 of a shutter opening plate 34, which will be described later.

Further, the other end 12b of the release locking lever can be engaged with a release member (not shown). On the other hand, a control lever 16 is rotatably provided on the left side of the slit groove 10c.
8, it is biased clockwise. One end 16a of the control lever 16 is formed in the shape of an obtuse key, and protrudes near the left end of the slit groove 10c so as to be able to engage a pin 40 of a shutter closing plate 36, which will be described later. and the other end 16b of the control lever
faces the position where it is attracted to the electromagnet 20 for shutter speed control.

Furthermore, an elastic braking member 22 is provided at the right end of the slit groove 10b of the base plate 10. This elastic braking member 22 is made of silicone rubber and integrally molded, and protrudes to approximately half the width of the slit groove 10b, extends along the slit groove 10b, and engages with a pin 38 of a shutter opening plate 34, which will be described later. A bridge portion 22a, a slit hole 22b formed on the side of the bridge portion 22a so as to extend parallel to the slit groove 10b, and two mounting holes 21, 23.
It consists of a mounting portion 22c having the mounting hole 21,
23 are fixed to fixing pins 24 and 26 of the base plate 10. Furthermore, the left end of the bridge portion 22a described above is connected to the slit groove 10b from the outside of the slit groove 10b.
A sloped portion 22d is formed that continues to a position where it enters the inside. The pin 38 traveling from the left side climbs this inclined portion 22d and slides on the upper surface while deforming the bridge portion 22a. On the other hand, the slit groove 10c
An elastic braking member 28 is provided at the right end portion of. Like the elastic braking member 22 described above, this elastic braking member 28 is a bridge that protrudes to approximately half the width of the slit groove 10c, extends along the slit groove 10c, and engages with a pin 40 of a shutter closing plate 36, which will be described later. portion 28a, an inclined portion 28d at the left end of the bridge portion 28a, a slit hole 28b formed on the side of the bridge portion 28a so as to extend parallel to the slit groove 10c, and two mounting holes 27, 29.
The mounting portion 28c has the mounting hole 2.
Fixing pins 30 and 32 of the base plate 10 are inserted into 7 and 29, and the elastic braking member 28 is fixed to the base plate 10.

Behind the base plate 10, a shutter opening plate 34 and a shutter closing plate 36 are provided. The shutter opening plate 34 is formed with an opening 34a on the left side in the figure, a light shielding part 34b on the right side, and a pin 38 that loosely fits into the slit groove 10b of the base plate 10 is integrally fixed. Furthermore, the shutter opening plate 3
A rearwardly bent bent portion 34c is formed at the right end of the shutter closing plate 4, and is adapted to contact the right end of the shutter closing plate 36 from the right side. On the other hand, the shutter closing plate 36 has a light shielding part 36b on the left side in the figure, an opening part 36a on the right side, and a pin 40 that loosely fits into the slit groove 10c of the base plate 10 is integrally fixed thereto. The shutter opening plate 34 and the shutter closing plate 36 have respective openings 34
a, 36b or the light shielding parts 34b, 36b are the base plate 10
It is slidably attached to a guide mechanism (not shown) so as to overlap the exposure aperture 10a. They are constantly pulled to the right in the figure by springs 42 and 44, respectively.

In the shutter charge state, the shutter opening plate 3
4 is located on the left side in the figure against the spring 42, and the base plate 1
The tip of the pin 38 passing through the slit groove 10b of 0 is locked by the key part 12a of the release locking lever 12, and the light shielding part 34b is stopped at a position overlapping with the shutter opening 10a of the base plate 10. On the other hand, the shutter closing plate 36 is also located on the left side in the figure against the spring 44, and is engaged with the bent portion 34c of the shutter opening plate 34, so that the opening 34a is connected to the exposure opening 10a of the base plate 10.
It can be stopped at a position that overlaps with the When the release operation begins, the electromagnet 20 is energized and the control lever 16
One end 16b of the control lever 16 is attracted to prevent the control lever 16 from rotating counterclockwise. This causes the control lever 16 to lock the pin 40 of the shutter closing plate 36. Then, when the release locking lever 12 is rotated counterclockwise by a release member (not shown), the engagement between the hook portion 12a and the pin 38 of the shutter opening plate 34 is disengaged, so that the shutter opening plate 34 is released from the spring. 42, it runs rapidly. When the shutter opening plate 34 travels just before the position where it should stop, the pin 38 of the shutter opening plate 34 is moved to the elastic braking member 2, as shown in FIG.
2, and slides on the tip surface of the bridge portion 22a while pushing the bridge portion 22a toward the slit hole 22b and deforming it. The shutter opening plate 34 is braked and stopped by the restoring force of the elastic deformation of the brake member 22 and the frictional force generated between the pin 38 and the brake member 22 at this time. Once the pin 38 and the bridge portion 22a are engaged, the bridge portion 22a wraps around and holds the pin 38, and even when the pin 38 runs in the opposite direction, it is braked, so that the shutter opening plate 34
Bounce prevention is also performed. With the structure described above, the shutter opening plate 34 travels to a position where its opening 34a and the exposure opening 10a of the base plate 10 overlap and then stops. As a result, the exposure aperture 10 of the base plate 10
a, the opening 34a of the shutter opening plate 34 and the opening 36a of the shutter closing plate 36 overlap, and exposure of the film surface (not shown) begins. When the film surface is exposed for a predetermined period of time, the electromagnet 20 is demagnetized and the shutter closing plate 36 is moved by the biasing force of the spring 44.
The pin 40 pushes the control lever 16 away against the spring 18, so that the pin 40 and the control lever 16 are disengaged. Therefore, the shutter closing plate 36
moves rapidly due to the spring 44. When the shutter closing plate 36 travels just before the position where it should stop, the pin 40 engages with the elastic braking member 28 and is braked, as in the case of the shutter opening plate 34 described above. The shutter closing plate 36 then travels to a position where its light shielding portion 36b overlaps the exposure aperture 10a of the base plate 10, and then stops. As a result, the exposure of the film surface is completed.

Thereafter, when a winding operation is performed, the shutter opening plate 34 is pulled to the left in the figure against the spring 42 by a winding member (not shown). This causes pin 3
8 slides on the bridge portion 22a of the elastic braking member 22, the engagement between the pin 38 and the elastic braking member 22 is disengaged, and the pin 38 engages with the release locking lever 28 and stops at the charge position. Shutter closing plate 36
Since the pin 40 is pushed by the bent portion 34c of the shutter opening plate 34, the pin 40 also disengages from the elastic braking member 28 and stops at the charge position where it can engage the control lever 16.

FIG. 4 shows a modified embodiment of the anti-bound braking device. In this embodiment, the bridge portion 52a of the elastic braking member 52 that engages with the pin 50 is inclined so that it protrudes more into the slit groove 54a of the base plate 54 as the pin 50 approaches the travel end position. It is formed by Note that the slit hole 52b is surrounded by the bridge portion 52a and the mounting portion 52c. This allows the braking force to increase as the pin 50 moves further. Further, as the pin 50 travels, the pin 50 is deeply wrapped in the bridge portion 52a of the elastic braking member 52, so that the effect of preventing bounce is enhanced.

FIG. 5 shows another modified embodiment. In this embodiment, the bridge portion 60 of the elastic braking member 60
A protrusion 60e is formed in the middle of a. As a result, the pin 62 comes into contact with the protrusion 60e just before the end of travel, resulting in a strong braking action. At the same time, after the pin 62 passes over the protrusion 60e, the protrusion 60e more reliably prevents the pin 62 from bouncing. Note that the slit hole 60b is connected to the bridge portion 6.
0a and the mounting portion 60c.

FIG. 6 shows yet another modified embodiment of the anti-bound braking device. The elastic braking member 68 of this embodiment has a bridge portion 68a and a slit hole 6.
8b is formed to protrude further diagonally upward from the side of the mounting portion 68c of the braking member 68. The braking member 68 is installed so as to protrude further into the slit groove 72a of the base plate 72 as it advances in the traveling direction of the pin 70. When the braking member 68 is shaped like this, the connecting portion 68f at the right end of the bridge portion 68a can be bent downward, so that the amount of deformation of the entire bridge portion 68a can be increased, thereby increasing the braking force. can be varied continuously over a wide range.

7 and 8 show other embodiments of a braking device for preventing bounce of a shutter member of a camera. FIG. 7 is a perspective view, and FIG. 8 is a sectional view. In this embodiment, an elastic braking member 78 made of polypropylene rapidly travels and stops at a shutter plate 80.
A pin 82 is fixed to a part of the camera body (not shown). This elastic braking member 78
is a mounting part 78 in which mounting holes 77 and 79 are formed.
c, a pair of connecting portions 78g, 78h vertically rising from the mounting portion 78c, and the connecting portions 78g, 78
A relatively wide bridge portion 78a formed so as to extend between both tip portions of h is integrally molded.
Note that a slit space 78b is formed below the bridge portion 78a. On the other hand, the pin 82 is fixed to a camera body (not shown). This elastic braking member 78 and pin 82 are connected to the shutter plate 8.
0 is arranged to engage just before the end of travel.

In this way, the elastic braking member may be integrally fixed to the rapidly traveling member side, and the pin may be fixed to the fixed member side. Furthermore, if the elastic braking member is shaped as shown in FIGS. 7 and 8, it is possible to form a wider engagement surface with the pin without increasing the overall wall thickness. becomes possible.

9 and 10 show a modified embodiment of the embodiment of FIGS. 7 and 8. FIG. The elastic braking member 90 made of silicone rubber is a bridge shaped like a cylinder cut vertically in half and placed parallel to the running direction of a shutter plate (not shown) on a mounting plate 90c in which mounting holes 89 and 91 are formed. A portion 90a is formed,
Below the bridge portion 90a is a slit space 90b.
is formed. Note that an inclined portion 90d is formed at the left end of the bridge portion 90a. This elastic braking member 90 is fixed to a camera body (not shown) and faces a position immediately before the pin 88, which is integrally fixed to an unfixed shutter plate, ends its travel. If the elastic braking member 90 has such a shape, a constant and stable braking force can always be obtained from the beginning of engagement with the pin 88.

The elastic braking members of each of the above-described embodiments have a shape in which the slit hole is surrounded by the bridge portion and the mounting portion. If the elastic braking member has such a shape, positional accuracy of the mounting portion and the bridge portion can be obtained even if the elastic braking member is made by integral molding.

FIG. 11 shows an example of a bounce prevention braking device used in a reflecting mirror section of a single-lens reflex camera. The reflecting mirror 96 is rotatably provided around an axis 98, and is stopped in the optical path of the photographing lens 100 at an angle of 45 degrees with respect to the optical axis X by a mirror drive member (not shown) during viewfinder observation. The light from the lens 100 is reflected toward a pentagonal prism (not shown), and when photographing, just before the shutter member 102 opens, it rotates around the shaft 98 and bounces out of the optical path of the photographic lens, and the reflection mirror 96
This allows exposure to the rear film surface 101.
When the shutter member 102 finishes exposing the film surface 101, it returns to the position for viewfinder observation. A pin 104 is integrally fixed to the side of the tip of the reflecting mirror 96. On the other hand, an elastic braking member 10 made of nice polyethylene
6, a mounting part 106c has a shape that follows the locus of the tip of the reflecting mirror 96, and is fixed immediately to the side of the reflecting mirror 96, and has a bridge part 106a, a slit hole 106b and a bridge part at its upper and lower ends. A portion 106i and a slit hole 106j are formed. These bridge portions 106a and 106i are formed to engage with the pin 104 immediately before the reflecting mirror 96 stops at the viewfinder viewing position or the photographing position. As a result, the above-described bounce prevention braking device can prevent the reflection mirror 96 from bouncing out of the optical path of the photographing lens and when returning to the optical path of the photographing lens.
Braking and bounce prevention effects work.

In this way, the anti-bound braking device of each of the above-mentioned embodiments can be used not only for the shutter member of a camera but also for braking and preventing members that travel rapidly and suddenly stop, such as the reflective mirror of a single-lens reflex camera. be able to.

In the bounce prevention braking device of the present invention, the engaging member and the braking member are made of rubber or elastic synthetic resin bridges that engage during braking, so the coefficient of friction is large and a large braking force can be achieved with a small contact force. and the operation noise is quiet. In addition, since a slit space is provided on the side of the bridge part and the bridge part is easily deformed elastically, stable braking force can be obtained.Moreover, after the engaging member passes, the bridge part which had been elastically deformed becomes elastic. Since it returns to the locus of the engaging member and the engaging member is wrapped in the bridge portion, an excellent bouncing prevention effect is produced.

As in the embodiment, if the mounting portion is formed so that the elastic braking member is surrounded by the bridge portion, the slit space, and the slit space is surrounded by the bridge portion, it is difficult for the dimensions of each part to be misaligned even if the elastic braking member is integrally molded. .

Further, when the bridge portion of the elastic braking member is inclined with respect to the traveling direction of the traveling member, the braking force gradually increases, which helps in preventing bouncing and makes it easier to obtain a stable braking force.

Furthermore, if a protrusion is formed in the middle of the bridge portion, the effect of preventing bounce will be increased once the engagement member has crossed over.

Furthermore, if the entire bridge part is formed to flex, the bridge part can undergo two stages of elastic deformation: local elastic deformation of the part engaged with the engagement member, and elastic deformation in which the entire bridge part flexes. can vary widely.

[Brief explanation of the drawing]

FIGS. 1a and 1b are sectional views showing the principle of a conventional example. 2 and 3 show an embodiment in which the present invention is applied to a shutter member of a camera, with FIG. 2 being an exploded perspective view and FIG. 3 being an enlarged front view of the main parts. 4 to 6 are enlarged front views of essential parts showing other modified embodiments of the present invention. FIG. 7 and FIG. 8 show another embodiment, and FIG.
The figure is a perspective view, and FIG. 8 is a front sectional view. 9 and 10 show essential parts of still another embodiment, with FIG. 9 being a perspective view and FIG. 10 being a front sectional view. FIG. 11 is a side view showing the principle of an embodiment in which the present invention is applied to a reflecting mirror section of a single-lens reflex camera. 22, 28, 52, 60, 68, 78, 90,
106...Elastic braking member, 22a, 28a, 52
a, 60a, 68a, 78a, 90a, 106
a, 106i...Bridge part, 22b, 28b,
52b, 60b, 68b, 78b, 90b, 10
6b, 106j...slit hole, 22c, 28
c, 52c, 60c, 68c, 78c, 90c,
106c...Mounting part, 38, 40, 50, 62,
70, 82, 88, 104...Engaging member.

Claims (1)

[Claims for Utility Model Registration] 1. An engaging member and a control member, one of which is fixed to a rapidly moving traveling member, and the other is fixed to a fixed member, and the above-mentioned engaging member and a braking member are arranged to engage with each other immediately before the running member finishes running, wherein the braking member includes a mounting portion coupled to the fixed member or the running member, and a mounting portion coupled to the fixed member or the running member; a bridge part made of rubber or a synthetic resin having elasticity, which is connected to the part at at least two places and is installed to straddle between the connecting parts, and extends in the traveling direction of the traveling member and engages with the engaging member; and a slit space is formed between the two connection points, the space being formed to extend in the direction of extension of the running member and allowing elastic deformation of the bridge. Anti-bounce device. 2. The bounce prevention braking device according to claim 1, wherein the slit space is formed substantially parallel to the traveling direction of the traveling member. 3. After the bridge part is inclined with respect to the traveling direction of the traveling member and the engagement member starts to engage with the bridge part, the engaging member gradually increases the elasticity of the bridge part in a direction perpendicular to the traveling direction. The anti-bound braking device according to claim 2, which is characterized in that it is deformed. 4. The anti-bound braking device according to claim 1, wherein a protrusion is formed in the middle of the bridge portion so that the engaging member can ride over it. 5. The anti-bound braking device according to claim 1, wherein the bridge portion is formed to protrude outward from the side portion of the attachment portion so that the entire bridge portion is bent. 6. The anti-bound braking device according to any one of claims 1 to 5, wherein the traveling member is a shutter member of a camera. 7. The bounce prevention braking device according to any one of claims 1 to 5, wherein the running member is a reflective mirror of a single-lens reflex camera.