JPH063376Y2 - Focal plane shutter setting mechanism - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a setting mechanism for shifting a leading blade driving arm and a trailing blade driving arm in a focal plane shutter to a charged state.

[Prior art and its problems]

The front plane driving member and the rear blade driving member are set to a charged state manually or electrically to prepare for a new photographing after the focal plane shutter is finished.

In such a focal plane shutter, by rotating the setting member, the leading and trailing blades are opposed to the springs that bias the leading blade driving member to the open position and the trailing blade driving member to the closing position. The drive parts are held in the closed position and the open position, respectively, so that the photographing can be performed.

By the way, many conventional setting mechanisms of this type of shutter use a cam mechanism as a transmission mechanism between the setting member and the front and rear blade driving members, but when the cam mechanism is used, it is inevitable in manufacturing. Due to dimensional error or use over time, inconveniences such as variations in operating stroke, inferior transmission efficiency, and increase in set torque are likely to occur, resulting in a problem in durability. Further, there is a set mechanism using a link system, but in this case, there are drawbacks that the mechanism is relatively complicated, the space factor is bad, and the cost is disadvantageous.

[Purpose of device]

The present invention has been made in view of the above circumstances, and an object thereof is to eliminate the drawbacks of the above-described conventional cam type and link type setting mechanisms, simplify the mechanism, and have good transmission efficiency and durability. To provide a focal plane shutter setting mechanism with excellent performance.

[Outline of device]

The above-described object of the present invention is to provide a leading blade drive member that is rotatably held, and is provided with a habit of biasing the leading blade to rotate in the shutter opening opening direction of the leading blade, and a leading blade closed state of the leading blade drive member. A front locking member for holding the rear blade, a rear blade driving member that is rotatably held, and is provided with a biasing tendency of rotation of the rear blade in the opening closing direction of the shutter by a spring, and the rear blade driving member. A trailing locking member for holding the leading blade open state, a first setting member that engages with the leading blade driving member so as to shift the leading blade driving member to the leading blade closed state, and the trailing blade. A second set member that engages with the trailing blade drive member so as to shift the drive member to the leading blade open state, and the engagement between the first set member and the leading blade drive member, Roller provided on the first setting member A setting operation step with a roller provided on the leading blade driving member and arranged in proximity to a straight line connecting the pivot point of the first setting member and the pivot point of the leading blade drive member before the shutter is set. And the engagement between the second set member and the trailing blade drive member is performed by the roller provided in the second set member and the trailing blade drive member. In a pre-setting state, mutual rolling engagement is performed in a set operation process with a roller arranged in proximity to a straight line connecting the pivot point of the second set member and the pivot point of the rear blade drive member. This is achieved by providing a focal plane shutter setting mechanism as described above.

[Example of device]

The present invention will be described below with reference to the embodiments shown in FIGS. FIG. 1 is a plan view of an essential part showing a state before setting, FIG. 2 is a plan view of an essential part showing a state during setting operation, and FIG. 3 is a plan view of an essential part showing a state after setting. Each member shown is installed on the main plate of the shutter, which is omitted in the drawing. (Note that in FIGS. 2 and 3, the springs shown in FIG. 1 are omitted.) In the drawings, reference numeral 1 is a main set lever that constitutes a set member together with a sub-set lever described later, and is centered on the shaft 2. In addition to being rotatably held by the spring 3, the spring 3 is provided with a left-handed habit, so that it can be rotated only between the position shown in FIG. 1 and the position shown in FIG. 2 by a stopper (not shown). is set up. Reference numeral 1a is an operating portion of a main set lever 1 formed to drive a post-connection lever described later. Four
Is a roller pivotally supported by the main set lever 1, and can be engaged with a roller of a trailing blade drive arm described later. Reference numeral 5 denotes a sub-set lever rotatably held by a shaft 6, which is connected to the main set lever 1 via a connecting lever 7.
It rotates in conjunction with the rotation of the main set lever 1. A roller 8 is pivotally supported by the sub-set lever 5, and can be engaged with a roller of a leading blade drive arm described later.

Reference numeral 9 denotes a leading blade drive arm that is rotatably held about a shaft 10, and is given a right turning property by a spring 11 to
In the state before setting in the figure, further right-handed rotation abutting against a stopper (not shown) is prevented. Reference numeral 9a denotes a locked portion formed on the leading blade drive arm 9 and is the locked portion 9a.
Is engaged with a tip locking lever described later when the leading blade drive arm 9 is in a charged state. Reference numeral 12 denotes a pin implanted in the leading blade drive arm 9, and the leading blade (not shown) is driven by the pin 12 via the leading blade operating arm. At the position shown in FIG. The shutter aperture is open. A roller 13 is axially supported by the leading blade drive arm 9 and can be engaged with the roller 8. As shown in FIG. 1, in the state before the shutter is set, the roller 13 provided on the leading blade drive arm 9 is a shaft of the auxiliary set lever 5 which supports the roller 8 rollingly engaged therewith as described later. 6 and the axis 10 of the leading blade drive arm 9
It is located close to the straight line that connects with. Reference numeral 14 is a tip locking lever that is rotatably held about a shaft 15, and is a spring 16
In addition to imparting a left-handed turning property, a further left-handed rotation is blocked by a stopper (not shown) in the state shown in FIG. As will be described later, 14a is provided for mooring the locked portion 9a of the leading blade driving arm 9 so as not to rotate to the right when the leading blade driving arm 9 is rotated counterclockwise as shown in FIG. 2 for setting. It is a locking portion formed on the first locking lever 14.

Reference numeral 17 denotes a trailing blade drive arm that is rotatably held about a shaft 18, and is given a right-handed habit by a spring 19 and is an operating portion 17 for driving a trailing blade operating lever described later.
a and a locked portion 17b to be locked by a post-locking lever described later, and the roller 4 of the main set lever 1
A roller 20 that can be engaged with is pivotally supported. As shown in FIG. 1, in the state before the shutter is set, the roller 20 provided on the trailing blade drive arm 17 is a shaft of the main set lever 1 which supports the roller 4 which is rollingly engaged with the latter as described later. It is in a position close to a straight line connecting the shaft 2 of the trailing blade drive arm 17 and the shaft 2. Note that 17c is a rising portion of the trailing blade drive arm 17. Reference numeral 21 denotes a rear blade operation lever which is rotatably held about the shaft 18 and whose rightward rotation limit position shown in FIG. 1 is defined by a stopper (not shown). A leftward rotation habit is imparted by a spring 22. ,
The rear blade drive arm 17 is provided with a pin 23 that engages with the operating portion 17a and a small pin 24 that engages with a rear connecting lever described later. A spring 19 for urging the trailing blade drive arm 17 and a spring 22 for urging the trailing blade operating lever 21.
The spring force of the spring 19 is set to be larger than that of the spring 22. As a result, in the state before the setting shown in FIG. 1, the operating portion 17a pushes the pin 23 to move the rear blade operating lever 21. The rear blade operation lever 21 is rotated to the right rotation limit, and further right rotation is prevented at this position. The pin 23 of the trailing blade operating lever 21 drives the trailing blade (not shown) via the trailing blade operating arm. In the position shown in FIG. 1, the trailing blade closes the aperture of the shutter. It is in. Reference numeral 21a is a rising portion of the rear blade operation lever 21.

Reference numeral 25 is a rear connecting lever that is rotatably held about a shaft 26, and is given a right turning property by a spring 27.
The main set lever 1 includes a pressed portion 25a that is pressed by the operating portion 1a and an engaging portion 25b that engages with the small pin 24 of the rear blade operating lever 21. In the state shown in FIG. 1, the rear coupling lever 25 is prevented from rotating further clockwise by the engagement portion 25b contacting the small pin 23. Reference numeral 28 denotes a rear locking lever that is rotatably held about a shaft 29, and is given a right-handed habit by a spring 30. Right-handedness has been blocked. 28a
Is set to the rear blade drive arm 17 when the rear blade drive arm 17 is rotated counterclockwise as shown in FIG. 2 for setting.
3 is a locking portion formed on the rear locking lever 28 for mooring the locked portion 17b as shown in FIG.

In the above-mentioned configuration, when the main set lever 1 is turned clockwise as shown in FIG. 2 from the state before setting (immediately after the end of shooting) in FIG. 1 for setting, the connection lever 7 is intervened accordingly. Turn the sub-set lever 5 clockwise as well. By rotating the set levers 1 and 5 clockwise, the roller 4 of the main set lever 1 moves to the roller 20 of the trailing blade drive arm 17,
Further, the rollers 8 of the sub-set lever 5 are brought into contact with the rollers 13 of the leading blade drive arm 9, respectively, and the leading blade drive arm 9 is rotated counterclockwise against the spring 11 (while the spring 11 is being charged) to rotate the leading blade. While moving the aperture from the open position to the closed position, the rear blade drive arm 17 is also moved.
Against the spring 19 (while charging the spring 19)
Turn left. Since the force transmission at this time is the contact between the rollers, the frictional force is small, and even if one of the roller shaft supporting portions causes "stripping" or the like, the opposite roller is rotated and the set torque is rapidly increased. The leading and trailing blade drive arms 9 and 17 can be rotated extremely smoothly without any increase.

The trailing blade operating lever 21 slightly moves following the action of the spring 22 as the trailing blade driving arm 17 rotates counterclockwise, but the small pin 24 is engaged with the engaging portion 25b of the trailing connecting lever 25.
And is prevented from rotating further to the left, so that the trailing blade remains in the position of closing the aperture.

Then, when the main set lever 1 reaches the so-called overcharge position of its rightmost position (FIG. 2 shows this state), the actuating portion 1a of the main set lever 1 is locked by the rear connecting lever 25. The rear connecting lever 25 is rotated counterclockwise by coming into contact with the pressing portion 25a to disengage the engaging portion 25b from the small pin 24 of the rear blade operating lever 21. As a result, the trailing blade operating lever 21 rapidly turns counterclockwise to the position shown in FIG. 3 by the pulling force of the spring 22 to move the trailing blade from the closed position of the aperture to the open position, and at the same time, the trailing blade drive arm 17 The pin 23 on the operating portion 17a of
Lock.

After that, if the operating force to the main set lever 1 is released, the main set lever 1 and the sub set lever 5 interlocked with the main set lever 1 are released.
Is returned to its original position by the force of the spring 3 as shown in FIG.
Of the rollers 8, 13 via the auxiliary set lever 5
Is rotated counterclockwise by the engagement of and the locked portion 9a is locked by the first locking lever 1.
4, the locked portion 9a is locked by the front locking lever 14 after the locking portion 14a of FIG. After the left-handed locked portion 17b crosses over the actuating portion 28a of the rear locking lever 28, it is locked by the locking portion 28a of the rear locking lever 28 to hold the charged state in which the right rotation is blocked. Then, the set end state shown in FIG. 3 is reached. As is well known from the state of FIG. 3, the front locking lever 14 and the rear locking lever 28 are driven by an electromagnetic device or the like at appropriate timings for proper exposure, so that the front blade driving arm 9 and the rear blade driving arm 17 are driven. When the moorings are sequentially released, the leading blade drive arm 9 first moves the leading blade from the closed position to the open position, and the trailing blade drive arm 17 moves the trailing blade from the open position to the closed position via the trailing blade operating lever 21. After shifting, one shot (exposure) is completed and the first
It returns to the state of the figure.

In the above-described embodiment, the main set lever and the sub-set lever are provided as the set members, but the main set lever alone may be used to press and rotate the leading and trailing blade drive arms. The mounting points can be variously modified, and it is needless to say that all the various modifications without departing from the spirit of the present invention are included in the scope of the present invention.

[Effect of device]

As described above, according to the present invention, since the setting operation is performed by the contact between the rollers, the operation is smooth and the friction torque can be reduced, and the rotation of the other roller can be performed even if one roller "caws". Therefore, it is possible to provide a focal plane shutter setting mechanism having a simple mechanism and excellent durability as a whole, without a fear of causing a rapid increase in setting torque, and its practical value is high.

[Brief description of drawings]

Each of the drawings relates to an embodiment of the present invention. FIG. 1 is a plan view of a main part showing a state before setting, FIG. 2 is a plan view of a main part showing a state during a setting operation, and FIG. It is a principal part top view which shows a state. 1 ... Main set lever 4 ... Roller 5 ... Sub-set lever 8 ... Roller 9 ... Leading blade drive arm 11 ... Spring 13 ... Roller 14 ... Leading locking lever 17 ... Trailing blade drive arm 19 ...... Spring 20 …… Roller 21 …… Rear blade operation lever 25 …… Rear connection lever 28 …… Rear locking lever

Claims (1)

[Scope of utility model registration request] 1. A front blade driving member which is rotatably held and is provided with a habit of biasing the front blade to rotate in a shutter opening opening direction of a front blade, and a front blade closing state of the front blade driving member. And a front locking member for rotatably supporting the rear blade driving member, which is rotatably held by the spring, and is provided with a habit of biasing the rear blade to rotate in the closing direction of the shutter of the rear blade, and the front blade opening of the rear blade driving member. A rear locking member for holding the state, a first set member engaged with the front blade driving member so as to shift the front blade driving member to the front blade closed state, and a rear blade driving member. A second set member that engages with the rear blade drive member so as to shift to the rear blade open state, and the engagement between the first set member and the front blade drive member is the first set member. Roller and tip provided on the 1st set member In a setting operation step with a roller provided on the blade drive member and arranged in proximity to a straight line connecting the pivot point of the first set member and the pivot point of the leading blade drive member before the shutter is set. Mutual rolling engagement is performed, and the engagement between the second setting member and the trailing blade drive member is performed by setting the roller provided in the second setting member and the trailing blade drive member to set the shutter. In the previous state, it is carried out by mutual rolling engagement in the set operation step with the roller arranged in the vicinity of the straight line connecting the pivot point of the second setting member and the pivot point of the rear blade driving member. The focal plane shutter setting mechanism is characterized by