JPH0583892B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present applicant previously disclosed a shutter equipped with a counterweight in Japanese Patent Application No. 56-166088. This counterweight moves in a direction opposite to the direction of movement of the shutter in synchronization with the movement of the shutter, and has the function of canceling out vibrations caused by movement and stopping of the shutter. Two counterweights are provided exclusively for the leading blade group and the trailing blade group, but here one of the counterweights is placed in the upper part of the shutter board, that is, in the part between the finder optical system and the aperture. Ta. Therefore, the vertical width of this upper portion had to be made larger than that of conventional cameras, leading to an increase in the overall height of the camera.

In addition, in the case of a single-lens reflex camera, if the thickness (depth) of this upper part increases due to the placement of the counterweight,
The rotation axis of the reflex mirror located in the front of this upper portion is pushed further in front of the camera than in conventional models. Along with this, the pentaprism also moves forward, resulting in an increase in the depth of the camera.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks and provide a shutter equipped with a counterweight that can be built into the camera without increasing its size.

In order to achieve this object, the present invention includes a shutter substrate having an opening, a first light shielding member that is unfolded to cover the opening and then folded and retreats from the opening; a first counterweight that operates in synchronization with the operation of the first light-shielding member and in a direction opposite to the direction of its operation to cancel out vibrations and shocks that occur as the first light-shielding member moves and stops; a second light shielding member that is expanded from the state in which the light shielding member is retracted from the opening and covers the opening; and a second counterweight that cancels vibrations and shocks that occur when the second light shielding member moves and stops, and the first counterweight and the second counterweight are connected to the It was placed on one side of the opening.

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

FIG. 1 shows an embodiment of the present invention, in which substrates 1 and 2
and 3 are attached. The substrate 1 is located between a cartridge chamber on the left side and a film take-up chamber on the right side (none of which are shown), and has an opening (aperture) 11 in the center, and pins 4a and 4b on one side edge. ,4
c, 4d are planted. A leading blade driving lever 5 is rotatably supported on the pin 4a, a leading blade auxiliary lever 6 is rotatably supported on the pin 4b, a trailing blade auxiliary lever 7 is supported on the pin 4c, and a trailing blade driving lever 8 is rotatably supported on the pin 4d. has been done. A leading blade group 9 is caulked between the leading blade drive lever 5 and the leading blade auxiliary lever 6 by a known method so that the leading blade group 9 moves parallel to each other. Similarly, the rear blade drive lever 8 and the rear blade auxiliary lever 7 are crimped by a known method so that the rear blade group 10 moves parallel to each other. Here, leading blade group 9 and trailing blade group 10
There is a partition plate (not shown) between the two. Further, shafts 12 and 13 are installed in the leading blade drive lever 5 and the trailing blade drive lever 8, respectively. The shaft 12 is the substrate 2
The shaft 13 passes through an arc hole 14 provided in the substrate 3 and an arc hole 15 provided in the substrate 3, and the shaft 13 passes through an arc hole 16 provided in the substrate 2 and an arc hole 17 provided in the substrate 3. ing.

An aperture 11' is formed in the substrate 2, and a pin 19 is implanted therein to rotatably support the leading blade driving member 20. This drive member 20 has a locking portion 20a at its free end, and is biased counterclockwise by a spring 21 disposed between it and the substrate 2. Also, the shaft 12 is connected to the hole 20b.
penetrates through. Also, the pin 2 planted on the board 2
2 rotatably supports a counterweight 23. This counterweight 23 consists of a main body part 23a, an upright part 23b, and a charge arm 23c, and is biased clockwise by a spring 24 disposed between one end of the main body part 23a and the base plate 2, and the charge arm 23c is in contact with the shaft 12.

A locking member 25 having a locking portion 25a and a locking pawl 25b is relatively rotatably attached to a shaft 26 which is supported by the substrates 2 and 3 and is detachable from a charging system (not shown). The locking member 25 is connected to the locking portion 20a of the driving member 20 at the locking portion 25a.
, the main body portion 2 of the counterweight 23 is attached to the locking claw 25b.
It is possible to engage with a locking pawl 23d formed at the corner of the upright portion 3a and the upright portion 23b. Further, the locking member 25 is biased counterclockwise by a spring 27 disposed between the locking end 25a and the substrate 2, and is held by attraction by a magnet 28 against the biasing force. It's becoming like that.

Charge plates 29 and 30 and an urging plate 31 are fixed on the shaft 26, respectively. Of these, the charge plate 29 is connected to the locking member 2 by rotation of the shaft 26.
It can come into contact with a pin 61 erected at 5. Further, the shaft 26 is biased counterclockwise by a spring 32 stretched between a biasing plate 31 and a camera body (not shown). The charge plate 30 is capable of contacting a pin 38 erected on a locking member 36 rotatably fitted onto the shaft 26 . Locking member 3
6 has locking ends 36a and 36b, and is biased counterclockwise by a spring 62. The magnet 39 acts to attract and hold the locking member 36 against the biasing force of the spring 62.

A pin 33 is implanted on the substrate 3 to rotatably support the rear blade drive member 34, and the shaft 13 passes through the hole 34b. Further, the rear blade drive member 34 has a locking portion 34a and is biased counterclockwise by a spring 35 disposed between it and the base plate 3, and the locking end 34a is connected to the locking member 36. It is engageable with the locking end 36a. The other locking end 36b of the locking member 36 is engageable with a locking end 37a of a counterweight 37 that interlocks with the rear blade group 10. The counterweight 37 is rotatable around a pin 40 erected on the base plate 3, and is supported by a spring 4 disposed between the base plate 3 and the base plate 3.
1 in the clockwise direction. Further, a shaft 42 is installed on the counterweight 37.

The shaft 43 is rotatably supported by a camera body (not shown) and can be connected to and removed from a charge system (not shown). A charge lever 44 having arms 44a and 44b is attached to this shaft 43, and is biased counterclockwise by a spring 45 disposed between the shaft 43 and the camera body. The arm 44a is rotated by the rotation of the shaft 43.
is in contact with the shaft 12, and the arm 44b is in contact with the shafts 13 and 42, respectively. The rotation end of the charge lever 44 is regulated by a pin 46 against which the arm 44a abuts.

Next, the operation of this embodiment will be explained. First, I will explain how to charge the shutter. In the first stage of the winding operation of a camera winding lever or motor drive (not shown), the shaft 26 is rotated clockwise against the spring 32. Due to this rotation, the charge plate 2
9 and 30 also rotate clockwise, and each pin 6
Press 1,38. As a result, the locking member 25
7, the locking member 36 is also
Each rotates clockwise against the action of The locking member 25 and the locking member 36 are attracted and held by a magnet 28 and a magnet 39, respectively. After that, when the connection between the charge system (not shown) and the shaft 26 is released, the shaft 26 is rotated counterclockwise by the action of the spring 32 connected to the biasing plate 31, and the biasing plate comes into contact with the pin 47. When it reaches , the rotation stops and it returns to its original position.

In the second stage of charging, the shaft 43 is rotated clockwise against the action of the spring 45 by a charging system (not shown). At this time, the charge lever 44 also rotates clockwise, and the shaft 12 is rotated by its arm 44a.
The shafts 13, 42 are pushed by the arm 44b. Thereby, the shaft 12 rotates the leading blade group 9 clockwise via the leading blade drive lever 5, and rotates the leading blade driving member 20 clockwise against the spring 21. Accordingly, the counterweight 23 in contact with the shaft 12 is rotated counterclockwise against the action of the spring 24. The locking portion 20a of the leading blade driving member 20 passes over the locking end 25a of the locking member 25 near the end of its rotation and is locked with the locking end 25a. Further, the locking pawl 23b of the counterweight 23 also climbs over the locking pawl 25b of the locking member 25 and is locked by the locking pawl 25b.

On the other hand, the shaft 13 is pushed by the arm 44b and moves clockwise, causing the rear blade group 10 to rotate clockwise and the rear blade drive member 34 to rotate clockwise against the spring 35. make it move. Near the end of rotation of the trailing blade drive member 34, the locking portion 34a rides over the locking end 36a of the locking member 36 and is then locked with the locking end 36a.

Further, the shaft 42 is pushed by the arm 44b, and the counterweight 37 rotates counterclockwise against the spring 41.
Near the end of the pushing movement of the arm 44b, the locking pawl 37a passes over the locking end 36b of the locking member 36 and is then locked with the locking end 36b, completing the charging. Here, the magnets 28 and 39 lose their attractive force when energized, and maintain their attractive force when not energized.

Subsequently, from the state shown in FIG. 1 showing the completion of shutter charging, the connection between the shaft 43 and the charging system built into the camera body (not shown) is released. Then, the charge lever 44 is rotated counterclockwise by the action of the spring 45, and the arms 44a and 44b are separated from the shaft 12 and the shafts 13 and 42, respectively, and are retracted out of the movement locus of each of these axes. Note that the rotating end of the charge lever 44 is connected to a pin 4 installed upright on the camera body.
6 is regulated by the arm 44a coming into contact with the arm 44a.

Next, when a shutter button (not shown) is pressed, a mirror (not shown) is retracted out of the photographing optical path, and this retraction signal is energized to the magnet 28 via an electric circuit (not shown). Then, the attraction force of the magnet 28 disappears, the locking member 25 rotates counterclockwise by the action of the spring 27, and the rotation stops when the pin 61 comes into contact with the charge plate 29.

By rotating the locking member 25 in the counterclockwise direction, the locking ends 25a and 20a are engaged with each other, and the locking ends 25b and 2
3d are unlocked almost simultaneously. First, the leading blade driving member 20 whose locking portion 20a is released and the shaft 12 integrated therewith are rotated counterclockwise by the action of the spring 21. Since the shaft 12 is implanted in the leading blade drive lever 5, as the shaft 12 rotates counterclockwise, the leading blade driving lever 5 also moves to the pin 4.
Rotate counterclockwise around a. As a result, the leading blade group 9 is actuated, the opening is opened, and exposure is performed. On the other hand, the counterweight 23, which is released from the locking portion 23d, rotates clockwise by the action of the spring 24. The rotating end of the counterweight 23 is regulated by a pin 51 erected on the base plate 2 .

After a predetermined period of time has elapsed, the magnet 39 is energized by an electric circuit (not shown) and its attractive force disappears.
The locking member 36 rotates counterclockwise under the action of the spring 62, and stops rotating when the pin 38 comes into contact with the charge plate 30. The rotation of the locking member 36 releases the locking between the locking ends 36a and 34a and the locking between the locking ends 36b and 37a almost simultaneously.

The rear blade drive member 34 with the locking end 34a released and the shaft 13 integrated therewith are moved by the spring 35.
It rotates counterclockwise until it comes into contact with the pin 48. This rotation of the shaft 13 causes the rear blade drive lever 8 to rotate counterclockwise around the pin 4d, and the rear blade group 10 also rotates to close the opening.
Shooting ends. On the other hand, the counterweight 37, which is released from the locking portion 37a, rotates clockwise under the action of the spring 41 until it comes into contact with the pin 49.

As described above, in this embodiment, the rotation of the leading blade drive lever 5 in the counterclockwise direction, that is, the leading blade group 9
The counterweight 23 rotates clockwise as it moves upward, and the counterweight 37 rotates as the rear blade drive lever 8 rotates counterclockwise, that is, as the rear blade group 10 moves upward. By rotating clockwise, the vibrations that occur as the shutter moves and stops are canceled out. The counterweights 23 and 37 are installed on separate substrates 2 or 3, and the counterweight 23 is installed on the shutter substrate 1.
The counterweight 37 is located between the opening 11 of the shutter board 1 and the bottom of the camera (below the opening) and between the cartridge chamber (to the left of the opening). It is located opposite to the portion between the portion 11 and the bottom of the camera (below the opening).

However, the vibrations and shocks generated during shutter operation become the most problematic when the leading blade group 9 stops (at this time, the rear blade group 10 is still in the middle of operation, and there is a gap between it and the leading blade group 9. Therefore, the present invention only needs to include a counterweight 23 for the leading blade group that operates in the opposite direction in synchronization with the operation of the leading blade group 9, and a counterweight 23 for the trailing blade group. Combined weight 3
Having a 7 is not essential.

Note that the locking portion 20a of the leading blade driving member 20 and the locking claw 23d of the counterweight 23 are the locking members 25, respectively.
When the locking member 25 is to be locked by climbing over the locking ends 25a and 25b, the locking member 25 must be rotated slightly counterclockwise while being attracted and held by the magnet 28. After the locking member 25 is attracted and held by the magnet 28, the locking portion 20a or 23d of the driving member 20 or the counterweight 23 is attached to the locking portion 25 of the locking member 25.
This is because it is necessary to get over the points a and 25d to be locked. This part has the structure shown in FIGS. 2 and 3.

In FIG. 2, the locking member 25 is located at the bent portion 2.
5c, and stepped pins 66, 67 are implanted on this bent portion 25c. stepped pin 6
A suction plate 68 is attached to 6 and 67.
A spring 6 is provided between the suction plate 68 and the bent portion 25c.
9 are arranged.

Therefore, when the locking end 20a of the leading blade driving member 20 and the locking end 23d of the counterweight 23 respectively get over the locking ends 25a and 25b of the locking member 25,
The suction plate 68 remains attracted to the magnet 28,
The locking member 25 and pins 66, 67 rotate clockwise against the spring 69. And the locking end 20a
and 23d respectively get over the locking ends 25a and 25b, the locking member 25 rotates clockwise under the action of the spring 69 and returns to the locking position. Note that although illustration and description are omitted, the locking member 36 is also configured in the same manner.

FIG. 4 shows a second embodiment of the present invention, and shows a first embodiment of the present invention.
The pin 20 implanted on the leading blade drive member 20 without using the locking members 25 and 36 in the embodiment of
c and the groove cam 23g provided on the arm 23f of the counterweight 23, the leading blade driving member 20 and the balancing weight 23 are interlocked, and the leading blade driving member 20 is connected to the magnet 28.
It is designed to be held by suction. Similarly, the pin 34b and the counterweight 3 are implanted on the rear blade drive member 34.
The trailing blade drive member 34 and the counterweight 37 are interlocked by a groove cam 37c provided on the arm 37b of No. 7,
The rear blade driving member 34 is attracted and held by a magnet 39.

According to this embodiment, by adopting the link mechanism, in addition to the locking members 25 and 36, the shaft 2
6, 42, etc., and the overall structure is simplified.

In the two embodiments described above, one counterweight 23 was arranged behind the leading blade group 9 and the trailing blade group 10, and the other counterweight 37 was further arranged behind it. However, the relative positional relationship between these in the front and back direction of the camera can be changed, for example, as shown in FIG. 5.

In FIG. 5, partition plates 71, 72, and 73 arranged to overlap in the front-rear direction (left-right direction in the figure) have openings 71a, 72a, and 73 in the center.
a, a leading blade group 9 is located between the partition plates 71 and 72, and a trailing blade group 10 is located between the partition plates 72 and 73.
are arranged respectively. Partition plates 71 and 73
Relatively low height partition plates 76 and 7 are provided on both outside sides of the
7 is attached, and a counterweight 23 for the leading blade group 9 is attached below the opening 71a and between the partition plates 71 and 76, and below the opening 73a and between the partition plates 73 and 77. Counterweight 37 for rear blade group 10
are placed respectively. Then, the counterweight 23 descends in synchronization with the rise of the leading blade group 9, and the counterweight 37
descends in synchronization with the rise of the rear blade group 10. In FIG. 5, 81 is a photographing lens, 82 is a reflex mirror, 83 is a pentaprism, and 84 is a photographic lens.
is a film.

In this embodiment, unlike the previous two embodiments, there is no need to transmit the motion of the trailing blade group to the trailing blade counterweight through the through hole in the substrate on which the leading blade counterweight is pivotally supported. Configuration becomes easier.

It should be noted that the details of the present invention can be modified and improved as appropriate in addition to the above, for example, the counterweight 23 may be rotated below the opening 11 (the counterweight 23 may be
3), or the counterweights 23, 37 can be placed on the right side of the opening 11. Further, the camera is not limited to a single-lens reflex camera.

The effects of the present invention described above can be summarized as follows. In other words, (1) the lower part of the aperture has a certain vertical width because the aperture can only be lowered to a point where the film can avoid the various mechanical parts installed at the bottom of the camera; For that reason, even if you set
There is no need to increase the vertical width. (2) There is a space on either the right or left side of the aperture to pivotally support the shutter blade at one end and to install the shutter drive mechanism, and a counterweight is placed over this space. There is no need to increase the width for this purpose. (3)
In the case of a single-lens reflex camera, even if the thickness of the lower, right, and left portions of the aperture increases, the position of the rotation axis of the reflex mirror will not be affected.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing a first embodiment of the present invention, Fig. 2 is a partially enlarged plan view thereof, and Fig. 3 is a second embodiment of the present invention.
4 is an exploded perspective view showing a second embodiment of the present invention, and FIG. 5 is a sectional view showing a third embodiment of the present invention. Explanation of symbols of main parts, 1, 2, 3... board,
5, 8... Lead blade drive lever, 9... Lead blade group,
DESCRIPTION OF SYMBOLS 10... Rear blade group, 11... Opening (aperture), 23... Balance weight for leading blade group, 37... Balance weight for rear blade group, 25, 34... Locking member.

Claims (1)

[Scope of Claims] 1. A shutter board provided with an opening; a first light shielding member that is unfolded to cover the opening and then folded and retracted from the opening; and the first light shielding member a first counterweight that operates in synchronization with the operation and in the opposite direction to the operation direction to cancel out vibrations and shocks that occur as the first light shielding member moves and stops; and a first counterweight that is folded and retracted from the opening. a second light shielding member that is expanded from the opened state to cover the opening; and a movement of the second light shielding member that is activated in synchronization with the operation of the second light shielding member and in a direction opposite to the operating direction of the second light shielding member. and a second counterweight that cancels vibrations and shocks that occur when the shutter is stopped, and the first counterweight and the second counterweight are located on one side of the opening of the shutter board. A shutter equipped with a counterweight. 2 The first and second light shielding members each have one end pivotally supported by a driving portion disposed on either the left side or the right side of the shutter board, and the first and second light shielding members
2. The shutter according to claim 1, wherein both the second counterweight and the second counterweight are disposed below the opening of the shutter substrate. 3 The first counterweight and the second counterweight are:
2. The shutter according to claim 1, wherein the shutters are arranged so as to at least partially overlap in the optical axis direction. 4. The first counterweight, the first light-shielding member, the second light-shielding member, and the second counterweight are arranged one on top of the other in the above order. Shutter according to scope 3.