JPH046012Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention superimposes two sets of blades each consisting of a plurality of thin plates using two sets of blade operating members rotatably arranged on the sides of the mapping window. The present invention relates to a focal plane shutter for a camera that is expanded to open and close a mapping window, and more particularly to a stopper device for each blade operating member when the shutter is opened and closed.

[Prior art and its problems]

In this type of focal plane shutter, the operating ranges of the open blade group and the closed blade group are different, so stoppers for the blade operating members of each group must be provided separately, that is, two stoppers are required. It was necessary. Therefore, in a system in which the function of the blade group is sequentially switched between opening and closing for each operation, four stoppers are required, which limits the placement position of the stoppers, complicates the structure, and increases the number of stoppers. The disadvantage was that the number of caulking points increased, which increased the number of assembly steps.

On the other hand, in the well-known focal plane shutter in which the leading blade group and the trailing blade group run in the same direction,
For example, if both ends of the long groove in which the pin of the operating member moves are used as stoppers, the groove end becomes the initial traveling position, so the error in machining the long groove will vary in the time from the initial traveling position of both blade groups until they cross the mapping window. will occur.

For this reason, it is possible to control the exposure time using a circuit equipped with a detection member such as a switch that detects the running position of the blade group, but this method has the disadvantage of requiring two or more detection members and making the control complicated. .

This point is also the same in a focal plane shutter in which the blade group moves back and forth, and since there are four stoppers, there is a problem that variations due to processing errors further increase.

[Purpose of invention]

An object of the present invention is to provide a stopper device that can reduce the number of stoppers by half and simplify the structure by making the stopper also serve as a stopper for each blade operating member of each blade group in a focal plane shutter. .

[Summary of the idea]

The present invention is a focal plane shutter that opens and closes a mapping window by superimposing and deploying two sets of blades, and by devising the shape of the two sets of blade operating members, the members set equal reciprocating momentum. This objective is achieved by arranging stoppers at both limit positions of the reciprocating movement, with which a certain portion of each can abut at the same position.

[Example of idea]

Embodiments of the present invention will be described below based on the drawings.

Reference numeral 1 denotes an intermediate plate disposed between two sets of blades, which will be described later, and forms a mapping window 1a.

2, 3, 4, and 5 in the drawings are a first main blade operating member, a first auxiliary blade operating member, a first slip forming blade, and a first auxiliary blade, which constitute the first blade group arranged above the intermediate plate 1. It's a feather. The first slit-forming blade 4 is pivotally connected to the members 2, 3 by support shafts 4a, 4b, and the first auxiliary blade 5 is pivotally connected to the members 2, 3 by support shafts 5a, 5b.

6, 7, 8, and 9 in the drawings are a second main blade operating member, a second auxiliary blade operating member, a second slit forming blade, and a second blade operating member constituting the second blade group arranged below the intermediate plate 1. It is an auxiliary blade. The second slit-forming blade 8 is pivotally connected to the members 6, 7 by support shafts 8a, 8b, and the second auxiliary blade 9 is pivotally connected to the members 6, 7 by support shafts 9a, 9b.

The first main blade operating member 2, the first auxiliary blade operating member 3, the second main blade operating member 6, and the second auxiliary blade operating member 7 are provided with support between the shutter upper plate and base plate (not shown), respectively. Axes 2a, 3a and 6
It is pivotally connected by a and 7a.

Furthermore, a recess 2b is formed in a part of the first main blade operating member 2.
However, there is also an arm portion 3b in a part of the first sub-wing operating member 3.
Similarly, a recess 6b is formed in a part of the second main blade operating member 6, and an arm part 7b is formed in a part of the second auxiliary blade operating member 7.

The recess 2b and arm 3b on the first blade group side, and the recess 6b and arm 7 on the second blade group side.
b are set so that the amount of reciprocating motion is equal at the same position, that is, between the stoppers 10 and 11 supported between the shutter upper plate and the base plate.

Therefore, in the illustrated state, when the first blade group functions as an open blade and the second blade group functions as a closed blade, the first blade group functions as the first slit forming blade 4 and the second blade group above the mapping window 1a. The final position of the opening operation for superimposing the auxiliary blades 5 is limited by the concave portion 2b of the first main blade operating member 2 coming into contact with the stopper 10, and the second blade group faces the mapping window 1a, and the second slit forming blade 8, The final position of the closing operation to expand the second auxiliary blade 9 is the second auxiliary blade operating member 7
The arm portion 7b abuts against the stopper 10 and is restricted.

Further, when the functions of each blade group are reversed and the opening/closing operation is performed after the above-mentioned state, the final position of the opening operation of the second blade group is when the concave portion 6b of the second main blade operating member 6 is the stopper, as shown in the figure. The final position of the closing operation of the first blade group is limited by the arm portion 3b of the first sub-operating member 3 coming into contact with the stopper 11.

Note that the operation of sequentially switching the function of each blade group between opening and closing for each operation is performed when the members 12 and 13 fitted in the long grooves 2c and 6c formed in the main blade operating members 2 and 6 are This can be achieved, for example, by driving a motor that rotates in forward and reverse directions by switching the current direction, or by an electrostrictive or magnetostrictive element whose displacement direction is reversed.

[Effect of idea]

As described above, the focal plane shutter stopper device of the present invention, which opens and closes the mapping window by superimposing and deploying two sets of blade groups, reduces the number of blades by half by serving as a stopper for the blade operating members of each group. As a result, the structure is simple, the number of assembly steps can be reduced, and it is extremely effective in practice.

Furthermore, since both blade operating members come into contact with the same part of the stopper at the final position of the operation and stop, the interval from the initial position of the leading blade group to the opening of the mapping window and the interval from the initial position of the trailing blade group to the beginning of the opening of the mapping window in the next operation, and the distance between the leading blade group and the initial position of the trailing blade group The distance from the position to when the mapping window begins to be covered is determined by one stopper.

Therefore, the initial traveling positions of both blade groups can always be set equally, and even if a machining error occurs in the pin, the exposure accuracy is not affected, making it possible to obtain an apparatus with less variation and improved exposure accuracy. can.

[Brief explanation of the drawing]

The drawings are explanatory diagrams showing one embodiment of the present invention. 2b, 6b... recess, 3b, 7b... arm, 1
0,11...stopper.

Claims (1)

[Claim for Utility Model Registration] The mapping window is opened and closed by overlapping and deploying two sets of blades, each consisting of a plurality of thin plates, by two sets of blade operating members rotatably arranged on the sides of the mapping window. In a focal plane shutter, two sets of blade operating members move in the same direction at a predetermined time interval in one operation cycle, and the direction of movement is sequentially reversed in each operation cycle, so that one group of blades moves in the same direction at a predetermined time interval. When functioning as an open vane, the other vane group functions as a closing vane, and the two sets of vane operating members have respective positions at both limit positions of their reciprocating motion so that the reciprocating momentum is set equally. A stopper device characterized in that a stopper is arranged so that its parts can come into contact at the same position.