JP3536131B2 - Adjustment device for mirror bounce prevention - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for adjusting a mirror bounce preventing device of a single lens reflex camera.

[0002]

2. Description of the Related Art Conventionally, this type of device has been shown in FIG. In FIG. 4, the main mirror (not shown) has a semi-transmissive portion and is fixed to the main mirror holding frame 202.
The support member 203 is integrated with the main mirror holding frame 202. The shaft 205, the shaft 206, and the pin 207 are fixed to the support member 203. The shaft 205 is rotatably supported by the camera body (not shown). The sub mirror support member 213 is integrated with the sub mirror holding frame 212. The sub-mirror support member 213 is rotatably supported by the shaft 206. The pin 215 is fixed to the sub-mirror support member 213. The toggle spring 216 has a pin 2
It is bridged between the pin 15 and the pin 207. Axis 227
And shaft 218 and pins 219, 220 and 224,
It is fixed to a camera body (not shown). Eccentric pin 221
Is attached to a camera body (not shown) so that its rotation can be adjusted.

The main mirror receiver 222 is rotatably mounted about a shaft 218. Main mirror receiver 222
Has arms 222a and 222b, a bend 222c and a friction surface 222d. The arm 222a is in contact with the eccentric pin 221. One end of a spring 226 is attached to the tip of the arm 222b. Bend 222c
Is in contact with the main mirror holding frame 202. The brake lever 228 is rotatably provided on the shaft 227 and has a contact surface 2
28a. The other end of the spring 226 is attached to the brake lever 228. The spring 226 biases the main mirror receiver 222 around the shaft 218 in the counterclockwise direction and biases the brake lever 228 around the shaft 227 in the counterclockwise direction. Due to the biasing force of the spring 226, the arm 2
22a is pressed against the eccentric pin 221, and the contact surface 228
a is pressed against the contact surface 222d.

The mirror return spring 230 has one end fixed to the support member 203 and the other end fixed to a camera body (not shown). The main mirror holding frame 202 is biased in the counterclockwise direction around the bearing (not shown) of the shaft 205 by the mirror return spring 230. Here, the spring 226 has a stronger biasing force than the mirror return spring 230. Next, the operation of the conventional technique will be described. When the exposure of the film is completed by a known method, the main mirror holding frame 202 returns to rotate counterclockwise around the shaft 205 by the biasing force of the mirror return spring 230. And the main mirror holding frame 202
And the bend 222c collide with each other. The impact force causes the main mirror receiver 222 to rotate clockwise against the spring 226.

On the other hand, the main mirror holding frame 202 continues to rotate counterclockwise and collides with the pin 224. Then, here, it largely bounces in the clockwise direction against the mirror return spring 230. The sub-mirror 211 moves following this bound. At this time, in the conventional device, the direction of the light S3 toward the photometry and distance measurement unit 232 changes due to the sub-mirror 211 bouncing. If photometry and distance measurement are performed during this bound, an error will occur in the photometry value and distance measurement value. Therefore, it is necessary to wait for the start of photometry and distance measurement until this bounce is stopped (until the waiting time elapses).

[0006]

However, if the above-mentioned bouncing preventing device is provided in the conventional device, the waiting time can be shortened. If the bounce prevention device can be adjusted, it is possible to set the bounce prevention device so as to efficiently attenuate the bounce.

As shown in FIG. 2, after the front body 100 and the rear body 101 are assembled (after the camera body is assembled).
The moment of inertia of the mirror bounce prevention device is indicated by arrow A
Even if the adjustment is made from the direction, the cartridge chamber 101a of the rear body 101 becomes an obstacle. Therefore, in the state of the front body 100, adjustment of the mirror by 45 ° and adjustment of the moment of inertia of the mirror bounce preventive device must be completed.

However, a spring for raising the mirror from the observation position to the photographing position outside the optical path (mirror up) and, conversely, a spring for lowering the mirror from the photographing position outside the optical path to the observation position (mirror down) (FIG. 4). 230) to charge the rear body 101. Further, even in a camera in which a motor (not shown) performs a mirror up and a mirror down, this mirror driving motor (not shown) is attached to the rear body 101. A release device (not shown) for starting the raising of the mirror is also attached to the rear body 101. Therefore 4 of the mirror
If an attempt is made to adjust the position by 5 ° and the moment of inertia of the bounce preventive device before assembling the front body 100 and the rear body 101, the raising and lowering operations of the mirror may be performed manually or the mirror may be manually moved. There was a problem in that a new device for raising and lowering was required.

Further, when assembling the front body 100 and the rear body 101, the mirror mechanism provided on the front body 100 and the mirror-up spring and the charge mechanism provided on the rear body 101 are mechanically assembled. There is an error. Therefore, even if the mirror is adjusted by 45 ° and the moment of inertia is adjusted before the front body 100 and the rear body 101 are assembled, it is necessary to readjust them according to a mechanical assembly error that occurs during assembly.

Therefore, the present invention has been made in view of such a problem, and makes it possible to adjust the moment of inertia of the mirror bounce preventive device even after the front body 100 and the rear body 101 are assembled, for adjustment. The object is to eliminate the trouble of manually operating the mirror and to eliminate the need for a special adjusting device.

[0011]

In order to solve the above-mentioned problems, in the present invention, a mirror box (40, 41) and an observation position in the photographing optical path and photographing outside the photographing optical path are provided in the mirror box. Mirror member (1, 2,
3 and 4), the mirror member can be brought into contact with the mirror member at the observation position and rotatable about a predetermined rotation center axis (18), and the mirror member can be moved from the retracted position to the observation position. A mirror receiving member (25, 22, 18, 23, 27) that receives an impact generated when displaced, an adjusting member (27) capable of adjusting an inertia moment of the mirror receiving member with respect to the rotation center axis, and the mirror receiving member. A braking member (2) that abuts the member and frictionally brakes the mirror receiving member.
8) and 8) are configured as a mirror bounce prevention adjusting device, and the adjusting member is arranged so as to be adjustable from the inside of the mirror box.

[0012]

[Operation] After the front body and the rear body are assembled, the inertial moment of the mirror bounce preventive device can be adjusted from the inside of the mirror box, eliminating the trouble of manually operating the mirror to adjust the inertial moment. In addition, it is not necessary to provide a special device for raising and lowering the mirror.

Further, since the moment of inertia of the mirror bounce preventive device can be adjusted after the front body and the rear body are assembled, the mirror mechanism of the front body and the mirror-up spring and charge mechanism of the rear body, which are generated during the assembly of the body, etc. It is possible to adjust the moment of inertia of the mirror bound device including the mechanical assembling error between and, and it is possible to make an accurate adjustment based on the actual use.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the present invention, and the same members and directions as in FIG. 2 are represented by the same reference numerals. In FIG. 1, a main mirror 1 (a mirror member, a main mirror member, a first reflecting member, and a movable mirror) of a single-lens reflex camera has an observing position (first light, light beam) through which a finder (not shown) can be observed. 1 position). The main mirror 1 has a semi-transmissive portion 1a in its substantially central portion. The main mirror 1 is
The main mirror holding frame 2 (mirror member, holding member) is fixed and held. The support members 3 and 4 (mirror members) are
It is provided integrally with the main mirror holding frame 2. Support member 3
A shaft 5, a shaft 6 and a pin 7 are fixed to the shaft. A shaft 8, a shaft 9, and a pin 10 are fixed to the support member 4.

The shaft 5 passes through a hole 44b (shown in FIG. 3) of the side wall 44 of the mirror box (metal die casting),
It is rotatably supported by a side substrate 40 (substrate) made of metal (iron or the like 9). The side substrate 40 is arranged on the side of the mirror box side wall 44 opposite to the main mirror 1, and is fixed (fixed) to the mirror box side wall 44 with a screw (not shown).

On the side wall of the mirror box 44 (one side wall of the mirror box), only the contact portion with the side substrate 40 (substrate) projects toward the side substrate 40 (other than the contact portion with the side substrate 40, the side substrate). And a mirror box side wall). Therefore, the cross section of the mirror box side wall 44 is L-shaped. By forming the mirror box side wall 44 in this manner, it is possible to reduce the weight of the mirror box, that is, the weight of the entire camera and reduce the cost. Mirror box side wall 4
As for the surface accuracy of No. 4, it is sufficient to pay attention only to the surface accuracy of the contact portion with the side substrate 40, so that there is an effect that the yield as a product is improved at the time of manufacturing.

The shaft 8 is rotatably supported by the side substrate 41. The center lines of the shafts 5 and 8 are both LL lines. The sub mirror 11 (second reflecting member, sub mirror member) is fixed to the sub mirror holding frame 12. The sub mirror support members 13 and 14 are integrated with the sub mirror holding frame 12. The sub-mirror support member 13 is rotatably supported around the shaft 6. The pin 15 is fixed to the sub mirror support member 13. A toggle spring 16 is hung (tensioned) between the pin 15 and the pin 7.

The sub-mirror support member 13 is a toggle spring 1.
It is biased counterclockwise by 6. The sub-mirror holding frame 12 is pressed against the pin 20 by the biasing force. As shown in FIG. 3, the pin 7 penetrates an arc hole 44c (fitting hole) provided in the side wall 44 of the mirror box and an arc hole 40a (fitting hole) provided in the side substrate 40 to form a mirror. It projects outside the box. The sub-mirror support member 14 is rotatably supported around the shaft 9.

The center lines of the shafts 6 and 9 are both MM lines. The shaft 17 is fixed to the side substrate 40. Pin 19
And the pin 20 penetrates the holes 44d and 44f provided in the side wall 44 of the mirror box as shown in FIG.
It is fixed to the side substrate 40. Axis 1 as shown in FIG.
8 (mirror receiving member) penetrates a hole 44g provided in the mirror box side wall 44 and is rotatably fitted to a bearing 42 fixed to the side substrate 40.

As shown in FIG. 3, the eccentric pin 21 (mirror position adjusting member, second adjusting member) is provided on the side wall 4 of the mirror box.
4 is pierced through a hole 44h provided in the No. 4 and is attached to the side substrate 40 so as to be rotationally adjustable. The main mirror receiver 22 (mirror receiving member) is fixed (fixed) to one end of the shaft 18. The inertia lever 23 (mirror receiving member) is fixed (fixed) to the other end of the shaft 18. Therefore, the main mirror receiver 2
2 and the inertia lever 23 move integrally. The arm 22a of the main mirror receiver 22 is in contact with the eccentric pin 21.
The pin 25 (mirror receiving member) is fixed (fixed) to the main mirror receiver 22, and the tip end thereof is in contact with the main mirror holding frame 2. The inertia lever 23 has an arc-shaped friction surface 23a, and has a weight 27 (adjustment member, inertia moment adjustment member,
An inertia moment setting member, a first adjusting member, a mirror receiving member) are attached so as to be rotationally adjustable.

The weight 27 is a copper alloy (for example, phosphor bronze).
Metal materials such as metal and tungsten, and resin materials (non-metal materials) such as molds mixed with metal powder (metal material) (synthesized by mixing) (for example, "Metalon, a registered trademark of Daisei Industry Co., Ltd." Etc.)).
Since resin materials such as "metallon", copper alloys, and tungsten have a large specific gravity, the weight can be downsized, and as a result, the bounce prevention device can be downsized.
Furthermore, the cost of resin materials such as metallon and copper alloys is low, so that the cost can be reduced. Further, there is an effect that resin products such as metallon are easy to be molded and rust hardly occurs.

One end of a spring 26 is attached to the tip of the arm 23b of the inertia lever 23. This weight 27
It penetrates through a hole 40b (through hole) provided in the side substrate 40 and a hole 44a (adjustment hole) provided in the mirror box side wall 44. The top of the weight 27 projects from the inside of the mirror box (arrow B side) (visible from the inside of the mirror box).

Further, the weight 27 is an eccentric pin having an eccentric shaft 27b. The eccentric shaft 27b is caulked to the inertia lever 23 so as to be rotationally adjustable. As shown in FIG. 3, the weight 2
The head portion 27a (top portion) of No. 7 is provided with a square hole (hexagonal hole, fitting hole). When the square hole is rotated by a wrench (hexagonal wrench, rotary operation member) or the like, the weight 27 rotates about the eccentric shaft 27b. Weight 2 by this rotation
The distance between 7 and axis 18 changes. This weight 27 and shaft 18
When the distance between and changes, the moment of inertia of the inertia lever 23 also changes. In other words, by adjusting this distance change amount,
The moment of inertia of the inertia lever 23 can be adjusted.

The brake lever 28 (braking member) is the shaft 17
It has a contact surface 28a, and a spring 26 is attached to its tip. Spring 26
The (elastic member, first elastic member, absorbing member) urges the main mirror receiver 22 around the bearing 42 in the counterclockwise direction and the brake lever 28 around the shaft 17 in the clockwise direction. Due to this biasing force, the arm 22a is pressed against the eccentric pin 21 (mirror adjusting member, second adjusting member), and the contact surface 28a is pressed against (contacts) the friction surface 23a.

One end of the mirror return spring 30 (return spring, mirror down spring) is hooked on the tip of the pin 7.
The other end of the spring 30 has a pin 43 fixed to the side substrate 40.
Is hung on. The biasing force of the mirror return spring 30 biases the main mirror 1 around the shaft 5 and the shaft 8 in the counterclockwise direction. Due to the biasing force of the spring 30, the main mirror holding frame 2 is pressed (contacted) to the pin 25.

The spring 26 has a stronger biasing force than the biasing force of the mirror return spring 30. The drive lever 31 is attached to the camera body (not shown). The pin 10 is in the movement locus of the drive lever 31 (in the movement locus, movement region) and can come into contact with the drive lever 31. Next, the operation of this embodiment will be described.

When a release button (not shown) is pressed after the front body 100 and the rear body 101 are assembled, the drive lever 31 moves in the G direction in FIG. And the drive lever 31
Engages the pin 10 and raises the main mirror 1 (mirror up). At this time, the main mirror rotates clockwise about the shafts 5 and 8 against the mirror return spring 30. Eventually, the sub-mirror holding frame 12 and the pin 20 are brought into non-contact with each other (contact between the holding frame 12 and the pin 20 is released).
Then, the sub-mirror support member 13 rotates counterclockwise around the shaft 6 by the biasing force of the toggle spring 16. By this rotation, the arm 13a of the sub-mirror support member 13 and the pin 1
9 comes into contact with (contacts).

When the main mirror 1 is further raised, the urging force of the toggle spring 16 changes its direction and acts so as to rotate the sub-mirror support member 13 around the shaft 6 in the clockwise direction. As a result, this time the arm 1 of the sub-mirror support member 13
3b and the pin 19 come into contact (abut).
When the raising of the main mirror 1 (mirror up) is completed, the main mirror 1 comes into contact with a stopper fixed to the camera body (not shown) and stops. Hereinafter, the stop position of the main mirror 1 is referred to as a shooting position. At this time, the main mirror holding frame 2 and the sub mirror holding frame 12 are brought into contact with each other by the biasing force of the toggle spring 16, and the semi-transmissive portion 1a is shielded from light. After this, shutter (not shown)
Operates to perform the exposure operation on the film.

After the exposure operation on the film is completed, the drive lever 31 moves in the direction opposite to the G direction in FIG. Following this, the main mirror 1 rotates counterclockwise around the axes 5 and 8 by the biasing force of the mirror return spring 30 and is displaced (mirror down) from the photographing position to the observation position.
When the main mirror 1 reaches the observation position, the pin 25 collides with the main mirror holding frame 2. Due to this collision, the main mirror 1
The kinetic energy from the photographing position to the observation position is transferred to the main mirror receiver 22 via the pin 25. This collision causes the main mirror receiver 22 to rotate clockwise around the bearing 42. At this time, while observing the change of the light S2 due to the bounce after the mirror is down by using the photometric distance measuring means 33, the bound of the main mirror 1 is minimized (the change of the light S2 is minimized, Or light S
2) is set in the shortest time), the weight 27 is rotated about the eccentric shaft 27b in the direction of the arrow B (from the mirror side of the mirror box, from the inside of the mirror box), and the weight 27 and the shaft 18 are rotated. Adjust the distance. This distance adjustment is to adjust the moment of inertia of the inertia lever 23.

The kinetic energy obtained by the main mirror receiver 22 due to the collision between the main mirror 1 and the pin 25 is transferred to the main mirror receiver 2.
When 2 rotates, it is stored as strain energy in the spring 26, and the contact surface 28a and the friction surface 23a are also stored.
It is converted into heat energy by the frictional force between and and is dissipated. Eventually, the main mirror receiver 22 stops rotating clockwise. After that, the main mirror receiver 22 starts rotating counterclockwise due to the urging force of the spring 26. This rotation causes pin 25
And the main mirror holding frame 2 collide with each other for the second time. However, at the time of this second collision, the kinetic energy of the main mirror receiver 22 is already dissipated by the friction between the contact surface 28a and the friction surface 23a when the main mirror receiver 22 rotates counterclockwise. . Therefore, the main mirror 1 hardly bounces even if the pin 25 and the main mirror holding frame 2 collide for the second time.

[0031]

As described above, according to the present invention, the inertia moment of the mirror bounce preventive device can be adjusted from the inside of the mirror box even after the front body and the rear body are assembled, so that the inertia moment is adjusted. Therefore, the inconvenience of manually operating the mirror can be eliminated, and it is not necessary to provide a special device for raising and lowering the mirror.

Further, after the front body and the rear body are assembled, the moment of inertia of the mirror bounce preventive device can be adjusted, so that the mirror mechanism of the front body and the mirror-up spring and charge mechanism of the rear body, which are generated during the body assembly, are generated. It is possible to adjust the moment of inertia of the mirror bound device including the mechanical assembling error between and, and it is possible to make an accurate adjustment based on the actual use.

[Brief description of drawings]

FIG. 1 is a perspective view of a mirror bound prevention device using the present invention.

FIG. 2 is an exploded view of a camera body into a front body and a rear body.

FIG. 3 is a view of the side wall of the mirror box as viewed from the inside of the mirror box.

FIG. 4 is a diagram showing a conventional mirror device.

[Explanation of symbols for main parts]

1 primary mirror 2 Main mirror holding frame 3, 4 support members 18 axes 21 Eccentric pin 22 Main mirror receiving 23 Inertial lever 23a Friction surface 25 pin 26 springs 27 weights 28 Brake lever 28a contact surface 40, 41 Side substrate 42 bearing 44 Side wall of mirror box 100 front body (body in front of camera) 101 rear body (camera rear body)

Claims (8)

(57) [Claims] 1. A mirror box, a mirror member provided in the mirror box, the mirror member being displaceable between an observation position inside the photographing optical path and a photographing position outside the photographing optical path, and capable of contacting the mirror member at the observation position. And a mirror receiving member that is rotatably provided with respect to a predetermined rotation center axis and receives an impact generated when the mirror member is displaced from the retracted position to the observation position, and the mirror related to the rotation center axis. The adjusting member includes an adjusting member capable of adjusting the moment of inertia of the receiving member and a braking member that abuts on the mirror receiving member and frictionally brakes the mirror receiving member. An adjusting device for preventing mirror bounce, which is characterized by being installed. 2. The adjusting device for preventing mirror bounce according to claim 1, wherein the adjusting member is integral with the mirror receiving member. 3. The adjusting member is an eccentric pin, and the adjusting member adjusts the moment of inertia by adjusting a positional relationship between the rotation center shaft and the eccentric pin. Adjustment device for preventing mirror bound. 4. The mirror bounce preventing adjusting device according to claim 1, wherein the adjusting member is formed of a metal material. 5. The mirror bounce prevention adjusting device according to claim 4, wherein the metallic material is a copper alloy or tungsten. 6. The adjusting device for preventing mirror bounce according to claim 1, wherein the adjusting member is a mixed molded product of a non-metallic material and a metallic material. 7. The adjusting device for preventing mirror bounce according to claim 1, wherein one side wall of the mirror box is provided with an adjusting hole for adjusting the adjusting member. 8. A through hole which can penetrate the adjusting member,
The mirror bounce prevention adjusting device according to claim 7, further comprising a substrate fixedly provided on a side of the one side wall opposite to the side of the mirror member.