US3644026A

US3644026A - Stopper device for electrically operated shutter of a camera

Info

Publication number: US3644026A
Application number: US887438A
Authority: US
Inventors: Katuhiko Toda
Original assignee: Canon Inc
Current assignee: Canon Inc
Priority date: 1969-12-22
Filing date: 1969-12-22
Publication date: 1972-02-22
Anticipated expiration: 1989-02-22

Abstract

A stop device for holding an electrically operated camera shutter in a locked position is provided by a pair of arms pivotally mounted on a shaft with a release lever arranged to pivot the arms. In the locked position one of the arms engages a stop block on a rotatable disc while the other arm has a detent at its free end which engages within a notch in the circumferential periphery of the disc. The disc is associated with the shutter and is rotatable by the device which electrically operates the shutter. When the release lever pivots the arms to unlock the disc for rotation, one of the arms closes a switch which actuates a motor for rotating the disc. The release lever and the arm are spring biased so that the arms are positioned relative to the disc to engage it in the locked position after it completes one revolution. In locking the disc one arm contacts the stop block while the detent on the other arm drops into the notch on the disc and breaks the switch for stopping the motor driving the disc.

Description

United States Patent Toda [54] STOPPER DEVICE FOR ELECTRICALLY OPERATED SHUTTER OF A CAMERA [72] Inventor! Katuhlko Toda, Yokohamashi, Japan [73] Assignee: Canon Inet, Tokyo, Japan [22] Filed: Dec. 22, 1969 211 App1.No.: 887,438

[ 1 Feb. 22, 1972 Primary Examiner-Samuel S. Matthews Assistant Examiner-Michael L. Gellner Attorney-McGlew and Toren [57] ABSTRACT A stop device for holding an electrically operated camera shutter in a locked position is provided by a pair of arms pivotally mounted on a shaft with a release lever arranged to pivot the arms. In the locked position one of the arms engages a stop block on a rotatable disc while the other arm has a detent at its free end which engages within a notch in the circumferential periphery of the disc. The disc is associated with the shutter and is rotatable by the device which electrically operates the shutter. When the release lever pivots the arms to unlock the disc for rotation, one of the arms closes a switch which actuates a motor for rotating the disc. The release lever and the arm are spring biased so that the arms are positioned relative to the disc to engage it in the locked position after it completes one revolution. 1n locking the disc one arm contacts the stop block while the detent on the other arm drops into the notch on the disc and breaks the switch for stopping the motor driving the disc.

7 Claims, 11 Drawing Figures PATENTEDFEBZZ I972 3. 644, 026

SHEET 1 OF 2 INVENTOR KCHUhIkO Todo IQQZZJ 4% ATTORNEYS FIG.5

PATENTEDFEBZZ I972 3,644,026

lNVE/VTOR Kotuhiko Todo ag/MM ATTORNEYS STOPPER DEVICE FOR ELECTRICALLY OPERATED SHUTTER OF A CAMERA The present invention is intended to stop the electrically operated shutter of a movie camera at a predetermined locked position and at the same time to eliminate such fear as the shutter being released by shocks, etc., while the camera is being carried around.

In, conventional methods, a device is employed such that after the switch of the electric motor for driving the shutter is cut off by a release lever, the action of the shutter is continued by inertia then the shutter is stopped at a predetermined position, or, a device is employed so that a notched portion is provided at the circumference of a disk while a detent is provided so that it slidably contacts the disk by the force of spring when the release lever is released, and as said detent comes into engagement with the above-mentioned notched portion, the switch is cut off stopping the motor.

. However, in the former device when the inertia is not sufficient the shutter stops at a released state, while when the inertia is too great the shutter is released by rebound. In addition it has the shortcoming that the shutter may be released by shocks while the camera is being carried around. On the other hand the later device has such defect that the detent tends to jump off the notched portion, which require delicate adjustment for the shape of the notched portion and the detent. It has the further shortcoming that as the spring has to be made very strong, great power is required for operation of the release lever. The present invention provides a stopper device free of the above-mentioned shortcomings.

The present invention shall be described in reference to the attached drawings in which:

The drawings show an example of the present invention, wherein FIG. 1 is a front elevation of the shutter in a stopped state;

FIG. 2 is a side elevation viewed from the direction as shown by the arrow A in FIG. 1;

FIG. 3 is a front elevation of the shutter in motion;

FIG. 4 is a side elevation viewed from the direction as shown by the arrow B in FIG. 3;

FIG. 5 is a front elevation showing the state of the shutter just before it is stopped;

FIG. 6 through FIG. 11 show another example of the present invention wherein FIG. 6 is a front elevation of the shutter in a stopped state;

FIG. 7 is a side elevation viewed from the direction as shown by the arrow A in FIG. 6',

FIG. 8 is a front elevation of the shutter in motion;

FIG. 9 is a side elevation viewed from the direction as shown by the arrow Bin FIG. 8;

FIG. 10 is a front elevation of the shutter just before it is stopped and;

FIG. 11 is a front elevation showing the state when accidentally stopped.

FIG. I through FIG. 5 show an example of the present invention, wherein a shutter is, although not shown, directly connected to the shaft 2 of a disk 1. A stopper block 3 is provided on the disk I by securing a pin thereto, and at the same time a notched portion 4 is formed in the circumference of the disk. One end of a release lever 6 is rotatably supported by a shaft 5 which is provided at one side of said disk, and the release lever is pulled by stretching a spring 8 between the lever 6 and a fixed pin 7. An arm 9 extends from the lever 6 and a detent 10 which engages with the stopper block 3 is formed at the tip or free end of the arm. Further, one end of an arm 11 is rotatably supported by the shaft 5 and a detent 12, which comes into and engages with said notched portion 4, is formed at'the tip of the arm W, and a spring 15 is provided between the projections I3, 14 which are respectively provided on the arm 9 and arm II for pressing the arms 9 and 11 together, thereby the projection 14 is pressed against the arm 9. A switch 16 for breaking and closing the circuit ofa power source ofa electric motor for driving the shutter is made to engage with the above-mentioned arm 11. An insulating plate l7 is attached to the portion of contacting piece of the switch contacted by the arm 11.

FIG. I and FIG. 2 show the stopped state of the shutter, wherein the detent 12 engages with the notched portion 4 and the detent 10 contacts and engages with the stopper block 3. When the release lever 6 is pressed to the direction of the arrow a against the elastic force of the spring 8, the arm 9 rotates in an anticlockwise direction, releasing the detent I0 from the stopper 3 and at the same time the arm 9 pushes up the projection 14, and rotates the arm 11, simultaneously 1 releasing the detent 12 from the notched portion 4, as shown in FIG. 3 and FIG. 4. And as the switch 16 is pressed by the arm I], the circuit is closed and completed, the electric motor for driving shutter is activated and the shaft 2 connected to said motor rotates as shown by the arrow b. Thus as the disk I rotates as shown by said arrow, the shutter performs an opening and closing motion synchronously, with the ratio of 1:1 with said rotation.

Next, when the release lever 6 is released, this lever assumes its original position as shown in FIG. 5 by the elastic force of the spring 8. Therefore the arm 9 and detent 10 which are integrally made with the lever 6 will assume their respective original position as shown in the drawing. But, as the detent 12 of the arm 11 will be riding on the circumference of the disk I, the switch 16 still maintains its closed and completed state causing the electric motor to continue rotation. Therefore the disk 1 continues to rotate as shown by the arrow b and the shutter keeps its movement synchronized with the disk. And as the stopper block 3 contacts the detent 10 the rotation of the disk 1 is discontinuous and stopped. At the same time as the notched portion 4 faces the detent 12, the detent comes into said notched portion by the elastic force of the spring 15. That is, as they assume their original positions as shown in FIG. 1 and FIG. 2, the switch is opened, stopping the electric motor for driving the shutter, and the movement of the shutter and the disk I is completely stopped. Therefore, by interconnecting said shutter and disk 1 so that they make such linked movement the shutter is closed at said state, the shutter will be stopped always at closed state. As the detent 12 engages within the notched portion 4, there will be no such fear as the disk 1 being rotated by shocks, etc., thus releasing the shutter.

As explained above, in the device of the present invention as the electric motor continues its motion even after the release lever 6, which functions to activate and stop the shutter, is released, there is no such fear that the shutter is stopped at the opened state because of insufficient inertia, while there is no such fear that the detent I2 jumps off the notched portion 4 thus continuing the rotation because the movement of the stopper block 3 is surely stopped by the detent l0. At the same time, since the detent 12 comes into said notched portion when the shutter is stopped locking the disk in place, so that the disk will not be rotated in either direction, such possibilities as the shutter being opened by rebound at the time it is stopped or by shocks when the camera is carried around will be eliminated. Further, as the disk I is surely stopped by the stopper block 3 and the detent 12 comes into the notched portion 4, it is not necessary to provide strong elastic power for the

springs

8 and 15. Therefore the release lever can be operated smoothly and lightly and there will be no shortcomings when the detent 12 contacts the disk I such that the load on the electric motor suddenly increases causing irregular variation in the shutter speed.

In the above example, it is possible to provide another disk or arm rotating with same speed as that of the disk I, and to attach the stopper block 3 to said disk or arm.

FIG. 6 through FIG. 11 show another example of the present invention wherein a shutter is, although not shown, directly connected to shaft 22 of a disk 2-1. A square studshaped stopper block 2-3 is provided on this disk 21, and a notched portion 2-4 is formed in the circumference of said disk. A release lever 2-6, a lever 27 for stopping the disk and a lever 28 for fixing the disk are rotatably supported by a shaft 25 provided at one side of the above-mentioned disk so that each lever is supported independently from the others. Fixed pins 2-9 and 2-10 are provided at one side of the shaft 2-5 and a spring 2-11 is stretched between the lever 2-6 and the pin 2-9; At the same time a projection 2-12 which engages with said pin 2-10 is provided at the root portion of the lever 2-7. Further a projection 2-13 which engages with other levers 2-7 and 2-8 is provided on the release lever 2-6, and pins 2-14 and 2-15 are provided at levers 2-7 and 2-8 respectively. Both ends of wire springs 2-16 and 2-17 which are wound once or twice around the shaft 2-5 are made to contact in a pressing manner against the pins 240 and 2-14 and the pins 2-10 and 2-15, respectively. A detent 2-l8 which engages with the stopper block 2-3 is formed at the tip of the lever 2-7, and a detent 219 which engages with the notched portion 2-4 is provided at the tip of the lever 2-8, and a switch 2-20 for breaking and closing the power source circuit of the electric motor for driving its shutter is positioned so as to contacting the lever 2-8. As the contacting piece of the switch an insulating plate 2-21 is attached as that it will be pressed by said lever.

H6. 6 and FIG. 7 show the normally stopped state of the shutter, wherein the detent 2-l9 seats within the notched portion 2-4 and the detent 2-18 engages the stopper block 2-3. When the release lever 2-6 is pulled to the direction of arrow against the elastic force of the spring 2-11, the levers 2-7 and 2-8 are pressed up by the projection 2-13 and will rotate in an anticlockwise direction, therefore, the detent 2-18 is released from the stopper block 2-3 and at the same time the detent 2-19 liftsout of the notched portion 2-4, and the switch 2-20 will be pressed by the lever 2-8 and closed and completed as shown in FIG. 8 and FIG. 9. Thus the shutter driving electric motor is activated. causing the shaft 22 which is connected to said electric motor and the disk 2-1 fixed to said shaft and further the stopper 2-3 attached to the disk 2-1 to rotate as shown by arrow b, and at the same time the shutter makes such opening and shutting motion as making at least one cycle of opening and shutting every time the disk 2-1 makes one rotation. Next, when the release lever 2-6 is released, this lever 2-6 assumes its original position as shown in FIG. 10 by the elastic power of the spring 241. Therefore, the projection 2-13 comes out of contact with the levers 2-7 and 2-8, and the lever 2-7 comes back to its original position as shown in the drawing by the elastic power of the spring 2-16. At the same time the lever 2-8 is pressed by the elastic force of the spring 2-l7 and the detent 2-19 at itstip is pressed into contact with the circumference of the disk 2-1. In this state as the switch 2-20 remains in the closed and completed circuit state, the disk 2-] continues its rotation as shown by arrow b, and the detent 2-19 lightly and slidably contacts the circumference of the disk. As the stopper block 2-3 comes into contact with the detent 2-18, the rotation of the disk 2-1 is forcibly prevented and stopped. At the same time as the notched portion 2-4 faces the detent 2-19, this detent comes into said notched portion by the elastic action of the spring 2-17. That is, as soon as the stopper block 2-3 comes into contact with the detent 2-18, the detent 2-19 drops into the notched portion 24, or the rotation of the disk is stopped by the detent 2-18 and with a slight delay the detent 2-19 engages with the notched portion 2-4, thus the switch 2-20 is opened stopping the electric motor. Therefore the entire device will completely assume its original state shown in FIG. 6, stopping the action of the shutter. As said shutter is so connected to the shaft 2-2 so that the shutter takes the closed position at the state mentioned above, the shutter always stops at its closed state. As the detent 2-19 engages with the notched portion 2-4, such fears that the disk 2-1 might rotate due to shocks etc., while camera is being carried around, caus ing the shutter to be opened are eliminated. While the release lever 2-6 and the release lever 2-8 are held in place by the shaft 2-5 as being independent'to each other in the abovementioned example, these levers may be formed integrally. It

is also possible to provide another disk or arm which rotates at same speed as that of the disk 2-l and the stopper 2-3 is formed on said disk or arm.

As the electric motor continues to function even after the release lever 2-6 is released in the device of the present invention, there is no fear that the shutter may be stopped at its opened state due to insufficient inertia, and there is no fear that the detent 2-19 jumps off the notched portion 2-4 since the disk 2-1 is forcibly stopped by the interactive of the stopper 2-3 and the detent 2-18. Further, any fear that the shutter may be opened by rebound at the time of stopping or by shocks etc., while the camera is being carried around are eliminated because at the same time the shutter is stopped the detent 2-19 comes into the notched portion 2-4 fixing the disk 2-1 in place. In addition to above, as the disk 2 l is stopped and the detent 2-19 is made to come into the notched portion 24, it is not necessary to provide strong elastic power for springs 2-1 1, 2-16 and 2-17. Thus the release lever can be operated smoothly and lightly and there will be no shortcoming when the load on the electric motor sharply increases at Y the moment when the detent 2-19 comes in contact with the disk 2-1, causing irregular variation in shutter speed.

As the release lever 2-6 and the release lever 2-7 having the detent 2-18 are supported separately in the device of the present invention, the lever 2-6 resumes its original position irrespective of the movement of the lever 2-7, and along with this the detent 2-18 gradually engages with the stopper block 2-3 deeper, thus achieving the intended stopper function.

The stopper block 2-3 of the square stud shape, as in this example, may be easily formed by punching and bending a portion of the disk 2-1. In this case, as the detent 2-18 gradually comes down, the detent 2'l8 will engage with the corner portion of the stopper block 2-3 as shown in FIG. 11 and is strongly pressed by the rotating force of the disk 2-1, and the lever 2-7 is stopped at such position as shown in the drawing. However, as the lever 2-8 can be shifted without relation to this lever 2-7, the lever 2-8 comes into the notched portion 2-4, releasing the switch 2-20. Therefore the electric motor is stopped and said rotating force will cease, thus the lever 2-7 also resumes its original position shown in FIG. 6. Thus, in the device of the present invention, since the lever 2-8 for engaging with the switch can be moved without relation to the lever 2-7 for stopping, a sure stopping function is secured at all times.

What is claimed is:

l. A stop device for an electrically operated camera shutter for securing a member in a locked position which member is associated with the shutter and is rotatable my means of the device which electrically operates the shutter, wherein the improvement comprises that said member is mounted for rotation about an axis as the shutter is electrically operated, said member having a notched portion therein and a stop projecting from its surface, a pivotally mounted first arm positioned in the path of movement of said member as it rotates and arranged to engage said stop thereon, a pivotally mounted second arm positioned in the path of movement of said member as it rotates and arranged to engage within said notched portion of said member, a switch member for actuating the means electrically operating the shutter and rotating said member and being displaceable between an open and a closed position, said second arm arranged to contact and displace said switch member into the closed position when said second arm is displaced from said notched portion of said member, means for biasing said first and second arms toward said member in position to engage said stop and said notched portion respectively, so that said member can be secured in the locked position by said first and second arm and when said second arm engages within said notched portion it releases said switch member from the open position so that the electrical operation of the shutter and of the rotation of said member is discontinued.

2. A stop device, as set forth in claim 1, characterized in that a spring member is secured between said first and second arms so that said first and second arms act as a unit in response to said means for biasing said first and second'arms toward said member.

3. A stop device, as set forth in claim 2, characterized in that a shaft is arranged for pivotally mounting said first and second arms, a lever secured to said first arm for pivoting it about said shaft and displacing it from engagement with said stop and said spring member secured between said first and second arms providing the interconnection whereby said second arm is displaced from said notched portion.

4'. A stop device, as set forth in claim 3, characterized in that a second spring member is arranged for biasing said lever so that said lever acts on said first arm for biasing said first arm into position for engagement with said stop.

5. A stop device, as set forth in claim 1, characterized in that a shaft is arranged for pivotally mounting said first and second arms, a lever pivotally mounted on said shaft, a projection positioned on said lever for engaging said first and second arms when said lever is pivoted on said shaft for displacing said first and second arms from the locked position with said member.

6. A stop device, as set forth in claim 1, characterized in that said member comprises a disc, a shaft arranged for rotatably mounting said disc, said stop being secured to and extending from a side of said disc and said notched portion being formed in the circumferential periphery of said disc.

7. A stop device, as set forth in claim 3, characterized in that each of said first and second arms being spaced apart along the axis of said shaft, and each of said first and second arms comprising a first part extending outwardly from said shaft and a second part extending angularly from said first part at the end thereof spaced from said shaft for engagement with said stop and said notched portion respectively.

Claims

1. A stop device for an electrically operated camera shutter for securing a member in a locked position which member is associated with the shutter and is rotatable my means of the device which electrically operates the shutter, wherein the improvement comprises that said member is mounted for rotation about an axis as the shutter is electrically operated, said member having a notched portion therein and a stop projecting from its surface, a pivotally mounted first arm positioned in the path of movement of said member as it rotates and arranged to engage said stop thereon, a pivotally mounted second arm positioned in the path of movement of said member as it rotates and arranged to engage within said notched portion of said member, a switch member for actuating the means electrically operating the shutter and rotating said member and being displaceable between an open and a closed position, said second arm arranged to contact and displace said switch member into the closed position when said second arm is displaced from said notched portion of said member, means for biasing said first and second arms toward said member in position to engage said stop and said notched portion respectively, so that said member can be secured in the locked position by said first and second arm and when said second arm engages within said notched portion it releases said switch member from the open position so that the electrical operation of the shutter and of the rotation of said member is discontinued.

2. A stop device, as set forth in claim 1, characterized in that a spring member is secured between said first and second arms so that said first and second arms act as a unit in response to said means for biasing said first and second arms toward said member.

4. A stop device, as set forth in claim 3, characterized in that a second spring member is arranged for biasing said lever so that said lever acts on said first arm for biasing said first arm into position for engagement with said stop.