JPH0731350B2 - Focal length switch camera - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a focal length switching camera, and more specifically, it transmits the rotational force of a motor to a focal length switching system to switch the focal length of a taking lens. The present invention relates to a focal length switching camera.

[Conventional technology]

Most of the recent 35mm compact cameras move the conversion lens in and out of the optical axis in conjunction with the movement of the master lens in the optical axis direction. For example, wide-angle shooting (wide shooting) with a focal length of about 35mm and focal length of about 70mm. The telephoto shooting (telephoto shooting) can be selected and performed.

Further, as described in JP-A-60-163010, JP-A-61-35435, etc., the rotational force of a film feeding motor is controlled by a focal length switching system via a clutch mechanism composed of a planetary gear train. In some cameras, the moving barrel holding the master lens is moved to switch the focal length.

[Problems to be solved by the invention]

However, for example, the forward movement of the movable barrel from the body is performed by an urging means such as a coil spring, and the backward movement of housing the movable barrel inside the body uses the rotational force of a motor or the like against the elastic restoring force of the coil spring. In this case, there is a problem that the entire apparatus becomes large unless the rotational force of the motor is used efficiently.

Further, when converting the rotational movement of the motor into reciprocating movement via a slider crank mechanism or the like, a crank rotation control mechanism is required to stop the crank at a predetermined position. When this rotation control mechanism is mechanically constructed by means such as levers, it is necessary to swing each lever etc. by rotation of the crank. There is a problem that the whole becomes large.

[Object of the Invention]

The present invention is to solve the above-mentioned problems, and provides a focal length switching camera capable of efficiently using the rotational force of a motor to suppress the size increase of the motor and reducing the size and weight of the entire apparatus. The purpose is to

[Means for solving problems]

In order to achieve the above object, the present invention has a biasing means for biasing the master lens toward the telephoto position, a switching cam rotated by a motor, and the switching cam formed at unequal length intervals in the circumferential direction. Two stop parts for stopping switching cam rotation,
Stop means for engaging the stop portion to stop the rotation of the switching cam, a pushing portion eccentrically provided on the switching cam, and a master lens are linked, and are biased by the biasing means. It is equipped with a focal length switching lever that comes into contact with the pushing part and swings by the displacement of the pushing part due to the rotation of the switching cam to move the master lens in the direction of its optical axis. Of the above, the longer rotation area is used to bring the pusher into contact with the one closer to the mounting shaft of the switching lever to set the master lens to the telephoto position, and the two stop portions provide unequal length intervals. Among these, the shorter rotation area is used to bring the pushing portion into contact with the mounting shaft of the switching lever at the far side to set the master lens at the wide-angle photographing position.

[Action]

When the shooting lens is selectively switched between the wide-angle shooting position and the telephoto shooting position, the rotational force of the motor is transmitted to the focal length switching cam, and the rotary motion of the switching cam is switched via the pusher of the switching cam. The swing motion of the switching lever is converted into the reciprocating motion of the master lens. In this case, the rotation of the switching cam is stopped by two stop portions for stopping rotation of the switching cam, which are formed on the cam at unequal length intervals in the circumferential direction, and engaged with the stop portions. It is configured to be stopped by engagement with the stopping means that operates. Therefore, since the intervals between the respective stop portions are unequal lengths, one of the rotations at these intervals is large and the other is small. Accordingly, due to the difference in the rotation time and the rotation angle between the two, it is possible to disperse the swing of the various levers by the switching cam in correspondence with the magnitude of the rotation time and the rotation angle.
Therefore, when the rotation time and the rotation angle are larger, the switching cam does not simultaneously swing the various levers, and the rotational force of the motor can be efficiently used.

Further, among the movements of the master lens in the optical axis direction, the forward movement for feeding the master lens forward of the body is performed by the biasing means for biasing the master lens forward, and the backward movement for storing the master lens in the body is switched. Since it is performed by the lever, the backward movement must be performed against the bias of the biasing means. For this reason, the rotational force for swinging the switching lever can be increased by bringing the switching lever into contact with the pushing portion on the side away from the mounting shaft, and the rear side of the master lens, which requires more rotational force, can be increased. It is possible to move reliably. Therefore, even if a motor with a small rotational force is used, the master lens can be moved backward against the biasing means, and the size can be further reduced.

Further, when the master lens is moved forward, it contacts the pushing portion on the side closer to the mounting shaft of the switching lever, and the two stop portions use the longer rotation area of the unequal length interval. By the means, the momentum of forward movement can be reduced and the master lens can be slowly set to the telephoto shooting position. As a result, the impact of the biasing means does not occur at the time of setting to the telephoto shooting position, and the durability of each mechanical component can be improved.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In FIG. 13 showing a focal length switching camera embodying the present invention, a front plate 40 is provided with a tubular portion 41 projecting forward. The tubular portion 41 is provided with a lens cover opening / closing knob 42, and when the lens cover opening / closing knob 42 is slid, the pair of lens covers 43, 44 rotates to open / close the opening 45. In addition, the front plate 40 is provided with a tele / wide (hereinafter referred to as TW) switching knob 46. When this is pressed down, it is switched to wide shooting when set to the tele shooting state,
If the wide shooting is set, the shooting is switched to the tele shooting. As will be described later, the TW switching knob
Even if 46 is held down, it will not switch cyclically between tele and wide shots.

Further, a well-known finder window 48, distance measuring windows 49a and 49b, and a stroboscopic light emitting section 50 are provided above the front plate 40, and a release button 51 is provided above the front plate 40.

FIG. 1 shows an outline of the optical system. A lens holder 4 holding a master lens 3 is slidably fitted in the moving barrel 1 and is moved along the optical axis L in the moving barrel 1 by a known distance measuring device (not shown). You can move and adjust the focus. A plate 1a projects from one side of the movable barrel 1 and has a bearing portion.
1b is installed. This bearing 1b has an optical axis L
A guide rod 2 extending in the direction is inserted, and guides the movable barrel 1 when it moves between a telephoto shooting position where the master lens 3 is extended forward and a retracted wide shooting position. A coil spring 5 is inserted through the guide rod 2 and biases the movable barrel 1 toward the telephoto shooting position.

A conversion lens 6 is disposed behind the movable barrel 1, and the conversion lens 6 is moved in and out of the optical axis L of the master lens 3 by a lens loading / unloading mechanism 7 that is interlocked with the movement of the movable barrel 1. This lens access mechanism 7
Is the arm 7a with the conversion lens 6 attached to the tip.
A lens moving gear 7b to which the arm portion 7a is attached, and a gear 7d having a swinging arm portion 7c. A coil spring 7e is hooked on the arm portion 7a to urge the conversion lens 6 in the direction of inserting it into the optical axis L.

A behind shutter 8 is arranged behind the conversion lens 6. This behind shutter 8
As is well known, the shutter blades 8a and 8b are provided with two shutter blades 8a and 8b, and the opening and closing pin 8d is moved toward the fixed pin 8c that pivotally supports the shutter blades 8a and 8b. It can be rotated to open the shooting optical path. Also,
A diaphragm device 74 is attached to the rear portion of the movable barrel 1 as shown in FIGS.

A TW switching device 10 (see FIG. 4) is provided to move the master lens 3 and the conversion lens 6. In the TW switching device 10, as will be described in detail later, the first switching lever 12 swings to move the master lens 3 along the optical axis L, and the conversion lens 6 is inserted into the optical axis L. In order to move the master lens 3 and the conversion lens 6, as shown in FIG. 1, one end of the first switching lever 12 abuts on the cam surface of the second switching lever 13 and The pin 12d provided in the section is inserted into the long hole 1c of the plate 1a. The cam formed on the second switching lever 13 includes a non-displacement engaging portion 13a for holding the conversion lens 6 at the retracted position retracted from the optical axis L, and the conversion lens 6 is rotated to move to the optical axis L. It is composed of a displacement engaging portion 13b for inserting, and these are continuously formed. This second switching lever 13 is interlocked with the first switching lever 12 so that the shaft 13c
When it rotates about, the arm 7c is pushed via the slide lever 9 to rotate the gear 7d.

2 and 3 show a telephoto shooting state and a wide-angle shooting state. A fixed cylinder 55 is arranged in the cylindrical portion 41, and the movable cylinder 1 is slidably fitted therein.
Further, the lens covers 43 and 44 shown in FIG. 13 are rotatably arranged between the tube portion 41 and the fixed tube 55, and as shown in FIG. At times, the lens covers 43 and 44 can be opened and closed.

The behind shutters 8a and 8b are attached to a shutter substrate 56, and open and close a shutter opening 56a formed in the shutter substrate 56. This shutter substrate 56 is screw 5
It is fixed to the main body 58 through 7 and four holes 56b for mounting a fixed cylinder are provided. The four legs 55b formed on the fixed barrel 55 are inserted into these fixed barrel mounting holes 56b, and the fixed barrel 55 is fixed to the main body 58 via screws 59.

Behind the fixed cylinder 55, a holding plate 60 is fixed,
The guide bar 2 is supported between the holding plate 60 and the fixed cylinder 55. A mounting plate 61 is fixed to the inside of the fixed cylinder 55, and the lens loading / unloading mechanism 7 is mounted on the mounting plate 61.

Next, the TW switching device 10 will be described with reference to FIGS. 4 to 12. The TW switching knob 46 is linked to the TW subset slider 11 via a lever or the like (not shown), and when the TW switching knob 46 is operated, the TW subset slider 11 is slid to the left in the drawing.

The TW switching device 10 includes the first switching lever 12 described above.
And the second switching lever 13 and the first switching lever
Switching cam 14 for swinging 12 and this switching cam
A motor 15 that rotates 14 and a cam that switches this motor 15
A motor switch 16 that is activated to rotate 14, a motor switch lever 17 that engages with the switching cam 14 to perform a self-holding action of the motor switch 16, and a motor switch lever 17 when a switching operation force is applied. And a latch set lever 18 for turning the motor switch 16 to ON.

As described above, the motor 15 is also used for film feeding (winding and rewinding) in addition to TW switching, and is stored in the spool 15a for winding the film 65.
The rotational force of the motor 15 is transmitted to the transmission switching mechanism 20 as a clutch mechanism via the reduction gear train 19. The transmission switching mechanism 20 includes a sun gear 20a that is linked to the reduction gear train 19, an arm (arm) 20b that is coaxially attached to the sun gear 20a, and is rotatably attached to the arm 20b and always. Planetary gear 20c meshing with sun gear 20a
And the arm 20b as the sun gear 20a rotates counterclockwise in the figure.
Is composed of a film feed side gear 20d that meshes with the planetary gear 20c at the rotation end position when the is rotated, and a switching cam side gear 20e that also meshes with the planetary gear 20c at the other rotation end position. .

An engagement portion 20f that engages with the engagement portion 27b of the TW set slider 27 is formed on the arm 20b of the transmission switching mechanism 20. When the TW set slider 27 is in the initial position before the switching operation, the engaging portion 27b of the slider 27 is set in the arm 2
By pushing the engaging portion 20f of 0b, the arm 20b meshes the planetary gear 20c with the film feeding side gear 20d. On the other hand, at the time of TW switching, the TW set slider 27 is located in the left direction in the drawing, and is separated from the engagement portion 20f by the engagement portion 27b. Therefore, at the time of TW switching, the planetary gear 20c revolves clockwise and meshes with the switching cam side gear 20e by the clockwise rotation of the sun gear 20a, and otherwise the planetary gear 20c is forced to the film feeding side gear 20d. Are in mesh.

The rotation of the film feeding side gear 20d is caused by a gear 67 fixed to the take-up spool 15a via a gear train (not shown),
Rewinding gear via a one-way clutch (not shown)
Each is transmitted to 68. A rewinding claw 69 is fixed to the rewinding gear 68, and is connected to a cartridge shaft 71 of a cartridge 70 containing the film 65.

The switching cam 14 includes a gear portion 14a connected to the gear 20e on the switching cam side via an intermediate gear train 21, a circular cam portion 14b formed under the gear portion 14a, and a lower surface of the circular cam portion 14b. It is provided with an engagement pin 14c that is eccentrically planted, and is rotatably attached to a substrate (not shown) via a shaft. The circular cam portion 14b has two notches 1 with unequal length intervals in the circumferential direction.
4d is formed, and the peripheral surface between these two notches 14d is the first and second cam surfaces 14e, 14f (the 11th
(See Figures and 12). The notch 14d is for inserting the engagement protrusion 17a of the motor switch lever 17. Further, the engagement pin 14c pushes the swing restriction lever 23, the latch set lever 18, and the first switching lever 12 to swing these levers 23, 18, 12, as will be described later.

The first switching lever 12 is provided with a locking claw portion 12a for restricting rotation (counterclockwise rotation in the drawing) of the movable barrel 1 toward the tele side and an engagement pin of the switching cam 14. It is provided with first and second engaging edge portions 12b and 12e engaging with 14c, and is rotatably attached to the substrate by an attaching shaft 12c.
Further, as shown in FIG. 1, the first switching lever 12 is biased by a coil spring 5 that biases the movable barrel 1 forward so as to always rotate to the tele side. A swing restricting lever 23 having a locking projection 23a that locks the locking claw portion 12a is rotatably mounted via a mounting shaft 23b. The swing restriction lever 23 has a function of restricting the rotation of the first switching lever 12 toward the tele side, and is biased clockwise by the coil spring 23c. The tip portion 23d of the swing restriction lever 23 is provided on the switching cam 1
It is positioned within the movement locus of the four engagement pins 14c, and is configured to be pushed by the engagement pins 14c immediately after the rotation of the switching cam 14 and rotated by a predetermined angle in the counterclockwise direction in the drawing.
Therefore, when the switching cam 14 rotates, the swinging restriction lever 23 rotates counterclockwise by the engagement pin 14c, and the locking projection 23
The locking between the a and the locking claw portion 12a is released. This makes the first
It is possible to rotate the switching lever 12 of (1) to the tele side.

The first locking edge portion 12b has a shape of a quadrant of a circle which is a movement locus of the outer edge of the engagement pin 14c, and when the switching lever 12 is switched to the tele side (counterclockwise rotation). ) Contacts the engaging pin 14c. Therefore, the switching cam 14
When the engagement pin 14c comes into contact with the engagement edge portion 12b by the rotation of, the first switching lever 12 is kept at the position until the first 1/4 rotation of the switching cam 14 is completed, and the 1/4 rotation is performed. When it passes, the first switching lever 1 moves with the movement of the engaging pin 14c.
2 will also be rotated to the tele side. Further, the second engagement edge portion 12e is formed so as to be continuous with the first engagement edge portion 12b and slightly protrude from the first engagement edge portion 12b, so that the second engagement edge portion 12e is widened to the wide side of the switching lever 12. Is engaged with the engaging pin 14c at the time of switching (clockwise rotation).

As shown in FIGS. 11 and 12, the non-displacement engaging portion 13a of the second switching lever 13 is an arc that is a movement locus of the engaging portion 12f at the tip when the first switching lever 12 rotates. It is formed in a shape, and its length is approximately 3/4 of the moving stroke of the lever 12 when the moving barrel 1 moves from the telephoto side position to the wide side position. The displacement engagement portion 13b is located inside the extension line of the non-displacement engagement portion 13a, and is a substantially triangular recess into which the tip engagement portion 12f of the first switching lever 12 is inserted. Therefore, when the first switching lever 12 moves to about 3/4 of its moving stroke, the tip end engaging portion 12f and the non-displacement engaging portion 13a come into contact with each other.
Only the first switching lever 12 rotates, and the second switching lever 13 does not rotate. First switching lever
When 12 rotates more than 3/4 of its travel, tip engaging part 12f
Comes into contact with the displacement engaging portion 13b from the non-displacement engaging portion 13a, and the second switching lever 13 biased in the clockwise direction in the figure by the coil spring 7e causes rotational displacement of the first switching lever 12. Correspondingly, it will rotate clockwise. Therefore, when the movable barrel 1 is moved by 3/4 or more of its movement stroke,
In conjunction with this, the conversion lens 6 is inserted into the optical axis L.

The motor switch lever 17 has a cutout for the switching cam 14.
An engaging projection 17a that is inserted into 14d to prevent rotation of the switching cam 14 at the time of this insertion, and this engaging projection 17a is a notch 14d.
And a switch changeover piece 17b for turning off the motor switch 16 when positioned inside. In this motor switch lever 17, the engaging projection 17a is located in the cutout 14d to prevent the cam 14 from rotating and the motor switch 16 is turned off. When it comes out, the lock with the switching cam 14 is released and the motor switch
It is attached to the substrate via a shaft 17c so as to be rotatable between an unlocking position where 16 is turned on. Since the first cam surface 14e and the second cam surface 14f of the switching cam 14 have unequal lengths, the rotation angle of each time the switching cam 14 depends on the length of these cam surfaces 14e, 14f. It will change periodically.

As shown in FIG. 5, the latch set lever 18 engages with the engaging pin 14c to push the motor switch lever 17 to the locking position side, and when the switching operation force is applied, the motor switch lever 17 Is rotated from the locked position to the unlocked position. Therefore, the latch set lever
Reference numeral 18 denotes a latch engaging portion 18a with which a latch lever 25 for switching the motor switch lever 17 to the locking position or the unlocking position is engaged, the latch engaging portion 18a and the latch lever.
After the latch (latch) by 25 is released, the engaging pin 14
It is provided with first and second engagement pushing surfaces 18b, 18c for rotating the latch set lever 18 in the clockwise direction by pushing of c to again latch the latch engaging portion 18a and the latch lever 25. . The first engagement pushing surface 18b is a surface for contacting the engagement pin 14c when switching from the wide side to the tele side. The second engagement pushing surface 18c is a surface for contacting the engagement pin 14c when the tele side is switched to the wide side.

The latch set lever 18 is a motor switch lever 17
Is rotatably mounted on the substrate by a mounting shaft 17c of a motor switch lever 17 and is urged counterclockwise in the figure by a coil spring (not shown).
In addition, the motor switch lever 17 and the latch set leger 18
A torsion spring 24 for urging the motor switch lever 17 to the locking position side is interposed between and. Further, the latch lever 25 is biased counterclockwise in the figure by the coil spring 25a.

The transmission of the switching operation force from the TW switching knob 46 to the motor switch lever 17 is performed by the leftward movement of the TW subset slider 11, the transmission lever 26, the TW set slider 27 to which the transmission lever 26 is attached, and the latch lever. 25, by being sequentially transmitted to the latch set lever 18.

The transmission lever 26 is the engagement protrusion 11 of the TW subset slider 11.
It has a claw 26a that locks to a and is rotatably attached to the TW set slider 27 via a mounting shaft 26b. The transmission lever 26 is biased clockwise by a coil spring 26c in the figure. Further, when the transmission lever 26 is engaged with the engagement protrusion 11a which is the engagement portion of the TW subset slider 11 and is moved to the vicinity of the end of its movement, it hits the transmission lever 26 and engages the lever 26 with its claw 26a. A lock release pin 30 that swings so as to release the lock with the mating protrusion 11a is attached to the substrate.

The TW set slider 27 is attached to the substrate so as to be slidable in the same direction as the sliding direction of the TW subset slider 11 by an attachment shaft and a long hole through which this shaft penetrates. The TW set slider 27 and the TW subset slider 11 are biased rightward in the figure by coil springs 28 and 29.

Next, the operation of this embodiment will be described.

When taking a picture, first, the lens cover opening / closing knob 42 is slid to open the lens covers 43 and 44. This lens cover 43,
Main switch (not shown) when 44 is moved to open position
Is turned on, and the drive circuit of the motor 15, the shutter drive circuit, the distance measuring device, the strobe circuit, etc. are energized.

When the lens covers 43 and 44 are open, the wide shooting state is set as shown in FIG. 3, and the movable barrel 1 is set back to the position where the movable barrel 1 moves backward and enters the moving range of the arm portion 7a. In this wide-angle shooting state, when the release button 51 is pressed, the distance measuring device is activated to move the lens holder 4 along the optical axis L according to the subject distance, and the master lens 3
Adjust the focus of. After this focus adjustment, the behind shutter 8 is activated to expose the film 65. After this shutter operation, the motor 15 rotates, and its rotational force is transmitted to the transmission switching mechanism 20 via the reduction gear train 19. In this transmission switching mechanism 20, the planetary gear 20c is a film feeding side gear 20d.
The rotation of the motor 15 is transmitted to the film feeding side gear 20d. Since the rotation of the film feeding side gear 20d is transmitted to the gear 67 through the gear train, the take-up spool 15a rotates to wind the exposed film 65 around the outer circumference thereof and draw it from the cartridge 70. Set the exposure film to the exposure position. Further, the behind shutter 8 is charged in association with the film winding.

Next, when switching from the wide shooting state shown in FIG. 3 to the tele shooting state shown in FIG. 2, the TW switching knob 46 may be slid. When the TW switching knob 46 is slid, the TW subset slider 11 moves leftward in the figure in conjunction with this, and the state shown in FIG. 5 changes to the state shown in FIG. As a result, the TW set slider 27 also moves to the left in the figure via the transmission lever 26 that is locked to the engaging protrusion 11a of the TW subset slider 11. By this movement, the engagement protrusion 27c of the TW set slider 27 faces the notch 17d of the motor switch lever 17, so that the motor switch lever 17 is allowed to rotate counterclockwise.

Further, the latch projection 25a of the TW set slider 27 rotates the latch lever 25 in the clockwise direction, and the latched state between the latch lever 25 and the latch set lever 18 is released. As a result, the latch set lever 18 rotates counterclockwise in the figure, and the motor switch lever 17 also rotates counterclockwise via the torsion spring 24 hung between the latch set lever 18 and the engaging protrusion.
17a comes out of notch 14d. The rotation of the motor switch lever 17 turns on the motor switch 16, and the motor 15 is energized to rotate. By the rotation of the motor 15, the planetary gear 20c revolves around the sun gear 20a and meshes with the switching cam side gear 20e. As a result, the rotational force of the motor 15 is transmitted to the switching cam 14 via the switching cam side gear 20e and the intermediate gear train 21, and the switching cam 14 rotates clockwise.

Note that FIG. 6 shows a state immediately after the TW subset slider 11 has moved to the end of movement. By the movement of the slider 11 to the end of the movement, the transmission lever 26 comes into contact with the locking release pin 30 projectingly formed from the substrate and rotates counterclockwise, thereby locking the engaging projection 11a and the claw 26a. Is released,
The TW set slider 27 moves to the right in the figure and tries to return. However, since the engaging protrusion 27c of the TW set slider 27 comes to be locked in the notch 17d of the motor switch lever 17 rotated to the unlocking side, the TW set slider 27
Will never return completely. Therefore, in this state, since the engaging portion 27b does not contact the engaging portion 20f, the planet gear 20c is kept in mesh with the switching cam side gear 20e. Although the TW set slider 27 does not completely return, the transmission lever 26 and the TW subset slider 11
Since the engagement with the engaging projection 11a is released and the connection between the TW subset slider 11 and the TW set slider 27 is broken, even if the TW switching knob 46 is positioned on the switching side, It is possible to prevent the switching from being switched periodically.

When the switching cam 14 starts to rotate in the clockwise direction, as shown in FIG. 7, the swinging restriction lever 23 first rotates in the counterclockwise direction by the engagement pin 14c thereof. This makes the first
Since the locking claw portion 12a of the switching lever 12 and the locking projection 23a of the rocking regulation lever 23 are released, the first switching lever 12 rotates counterclockwise about the shaft 12c. The engaging edge portion 12b comes into contact with and follows the engaging pin 14c. However, since the engaging edge portion 12b has a quadrant arc shape, the first switching lever 12 is not rotated to the tele side until the switching cam 14 has completed 1/4 rotation.

Since the engagement pin 14c of the switching cam 14 and the first engagement push surface 18b of the latch set lever 18 come into contact with each other during this 1/4 rotation,
The latch set lever 18 is rotated clockwise in the figure, and is returned to the initial position by the latch lever 25 being locked. When the latch set lever 18 returns to the initial position, the spring 24 is charged, so that the motor switch lever 17 is biased clockwise in the figure. However, the circular cam part 14b
Since the tip of the engaging protrusion 17a is in contact with the peripheral surface of the motor switch lever 17, the motor switch lever 17 cannot rotate clockwise in the figure, and the motor switch 16 is maintained in the ON state. As a result, the motor switch 16 is self-held when switching from wide shooting to tele shooting.

As shown in FIG. 8, the first switching lever 12 has almost the same force as the switching cam 14 due to the elastic restoring force of the coil spring 5.
It rotates counterclockwise following the movement of the engagement pin 14c due to the rotational displacement of 1/4 or more. As a result, the movable barrel 1 is extended forward, and the master lens 3 is set at the telephoto shooting position. The positioning of the movable barrel 1 on the wide side is performed by the second
As shown in the figure, for example, the front surface of the moving barrel 1 is a fixed barrel 55.
It is done by hitting. Therefore, after the movable barrel 1 is extended forward and hits the fixed barrel 55, the forward movement of the movable barrel 1 is restricted, and thus the rotation of the first switching lever 12 is also restricted at this position.

The tip portion 12f of the first switching lever 12 has a coil spring 7
Since the second switching lever 13 is in contact with the cam surface of the second switching lever 13 biased by e, the second switching lever 13 is interlocked with the first switching lever 12. However, this second switching lever
13, the first switching lever 12 is approximately
Since the non-displacement engaging portion 13a contacts the one end portion 12f of the first switching lever 12 during the rotation of 3/4, even if the first switching lever 12 rotates, it does not follow this.
Then, as shown in FIG. 12, when rotating the remaining 1/4, one end 12f of the first switching lever 12 faces the displacement engaging portion 13b of the second switching lever 13, This second
The switching lever 13 rotates rapidly around the shaft 13c as a fulcrum. When the second switching lever 13 rapidly rotates, the lens moving mechanism 7 follows this via the slide lever 9, so that the swing arm portion 7a rotates counterclockwise and the conversion lens 6 is illuminated. Insert on axis L. Therefore, when the master lens 3 moves to a position sufficiently distant from the conversion lens 6, the conversion lens 6 rapidly rotates, and these lenses do not interfere with each other.

As shown in FIG. 9, when the switching cam 14 rotates about 1/2 or more, the engaging protrusion 17a of the motor switch lever 17 is inserted into the notch 14d, so that the motor switch lever 17 is moved to the initial position. Then, the motor switch 16 is turned off to stop the motor 15. Also, the motor switch lever
By the return of the initial position of 17, the engagement state between the engagement protrusion 27c of the TW set slider 27 and the notch 17d of the motor switch lever 17 is released, and the TW set slide 27 also moves to the right in the drawing to move to the fifth position. Return to the initial position as shown. With this return to the initial position, the engaging portion 20f of the arm 20b of the transmission switching mechanism 20 is pushed by the engaging portion 27b of the TW set slider 27, and the arm 20b is rotated counterclockwise. This arm 2
When 0b is rotated, the planet gear 20c is moved to the film feeding side gear 20d.
It will be forced to mesh with the side.

As a result of the above operation, the movable barrel 1 is extended forward through the fixed barrel 55 from the wide shooting state in which the movable barrel 1 is housed in the fixed barrel 55, as shown in FIG.
The telephoto photographing state in which the conversion lens 6 is inserted on the optical axis L at the rear of is switched to. The switching from the wide shooting state to the tele shooting state is performed using the first cam surface 14e of the switching cam 14. Since the first cam surface 14e is formed longer than the second cam surface 14f, the rotation angle and the rotation time of the switching cam 14 become longer than that of the second cam surface 14f, and this increase The swing control lever 23 and the latch set lever 18 are swung according to the rotation time and the rotation angle. Moreover, since these swings are sequentially performed, the load on the motor that rotates the switching cam 14 can be lightened without concentration of these swings.

Next, it is possible to switch from tele shooting to wide shooting by the same operation as the above-described switching from wide shooting to tele shooting. That is, when the TW switching knob 46 is slid, the motor switch lever 17 is pulled out from the notch 14a of the switching cam 14 as shown in FIG. 10, and at the same time, the motor switch 16 is turned on. The rotation of the motor 15 is switched by a gear train 19 and a transmission switching mechanism 20.
Transmitted to 14.

At the initial stage of the rotation of the switching cam 14, the second pushing surface 18c of the latch set lever 18 is pushed through the engagement pin 14c to return the latch set lever 18 to the initial position, and at the same time, the latch set lever 18 is pushed. It is locked by the latch lever 25. Then, when the switching cam 14 further rotates, the engaging pin 14c hits the engaging edge portion 12e of the first switching lever 12, so that the elastic restoring force of the coil spring 5 for urging the movable barrel 1 to the front side is resisted. The engagement pin 14c pushes the first switching lever 12 to rotate it in the clockwise direction and start the retreat of the movable barrel 1. At the same time, the tip of the first switching lever 12 pushes the engaging arm portion 13a of the second switching lever 13 as the first switching lever 12 rotates toward the wide-angle shooting side. The switching lever 13 rotates counterclockwise in conjunction with the rotation of the first switching lever 12 to retract the conversion lens 6 from the optical axis via the slide lever 9 and the lens loading / unloading mechanism 7 (see FIG. 1).

When the switching cam 14 continues to rotate, its engaging pin 14
By c, the first switching lever 12 is further rotated clockwise. When the first switching lever 12 is pushed to the maximum in the clockwise direction, as shown in FIG.
a rides over the locking projection 23a of the rocking restriction lever 23, and the locking claw portion 12a and the locking projection 23a are locked. This allows
The first switching lever 12 is locked at the telephoto shooting position by the swing restriction lever 23 and cannot rotate counterclockwise. Even after this locking, since the switching cam 14 slightly rotates, the engagement pin 14c moves to a position separated from the second engagement edge portion 12e, and the state shown in FIG. 5 is restored.

When the switching cam 14 and the first switching lever 12 return to the state shown in FIG. 5, the motor switch lever 17 enters the notch 14d of the control cam 14, so that the motor switch 16 is turned off and the TW set slider 20 is also moved. Return to the initial state. this
The TW set slider 20 disengages the planetary gear 20c from the switching cam side gear 20e and forcibly meshes with the film feeding side gear 20d. The switching from the telephoto shooting state to the wide-angle shooting state described above is performed by the second cam surface 14 of the switching cam 14.
done using f. Also, the engaging pin 14c of the switching cam 14
And the switching lever 12 are switching levers when the master lens 3 is switched from the telephoto shooting position to the wide shooting position.
Since the twelve mounting shafts 12c are brought into contact with each other on the far side, the first switching lever 12 can be swung with a large torque. Therefore, it becomes possible to easily swing the first switching lever 12 against the elastic restoring force of the coil spring 5 that biases the movable barrel 1 forward.

Incidentally, when the photographing of all the frames of the film 65 is completed, the reverse rotation of the motor 15 is automatically started as well known, and the rewinding claw 69 is rotated via the transmission switching mechanism 20. (See FIG. 4). When the rewinding claw 69 rotates, the exposed film 65 wound on the spool 15a is rewound into the cartridge 70.

In the above embodiment, the conversion lens 6 is inserted into the optical axis of the master lens 3 by switching the second switching lever 13 by interlocking with the first switching lever 12, but the present invention is not limited to this. However, the conversion lens 6 can be inserted into the optical axis L by using another mechanism.

Further, in the above embodiment, the photographing lens is configured by the master lens 3 that moves in the optical axis direction when the focal length is switched and the conversion lens 6 that is inserted in the optical axis of the master lens 3 during telephoto photographing. The invention can also use a zoom lens.

〔The invention's effect〕

As described above, according to the present invention, the switching cam is provided with the two stop portions for stopping the cam rotation at the unequal length intervals in the circumferential direction, and the unequal length intervals of the two stop portions are Since the master lens is set to the telephoto shooting position by bringing the pushing part into contact with the one closer to the mounting shaft of the switching lever by using the longer rotation area, the momentum of forward movement of the master lens by the biasing means is reduced. You can slowly set the master lens to the telephoto position. Therefore, the impact of the urging means does not occur at the time of setting to the telephoto shooting position, and the durability of each mechanical component can be improved.

Further, since the rearward movement of accommodating the master lens in the body is performed by the switching lever and the rearward movement is performed by contacting the pushing portion on the side away from the mounting shaft of the switching lever, the swinging of the switching lever is performed. It is possible to increase the rotational force for the movement of the master lens and to reliably move the master lens backward against the biasing force. Moreover, even if a motor having a small rotational force is used, the master lens can be moved in the backward direction against the biasing means, and the size can be further reduced.

Further, since the intervals between the respective stop parts are made unequal by the two stop parts, one rotation is large and the other rotation is small at the intervals. Accordingly, due to the difference in the rotation time and the rotation angle between the two, it is possible to disperse the swing of the various levers by the switching cam in correspondence with the magnitude of the rotation time and the rotation angle.
Therefore, when the rotation time and the rotation angle are larger, the switching cam does not simultaneously swing the various levers, and the rotational force of the motor can be efficiently used. As a result, even if a small motor is used, the focal length can be switched reliably, and the focal length switching camera can be made compact.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of a focal length switching camera of the present invention. FIG. 2 is a sectional view of an essential part of the focal length switching camera set in the telephoto shooting state. FIG. 3 is a sectional view of an essential part of the focal length switching camera set to the wide-angle shooting state. FIG. 4 is a perspective view showing the TW switching device. FIG. 5 is a plan view of the TW switching device shown in FIG. 6 to 10 are plan views for sequentially explaining the operation of the TW switching device. FIG. 11 shows the first and second images set in the wide-angle shooting state.
It is a top view which shows the relationship of a switching lever. FIG. 12 is a plan view showing the first and second switching levers set in the telephoto shooting state. FIG. 13 is an external view of a focal length switching camera of the present invention. 1 ... moving barrel 3 ... master lens 6 ... conversion lens 8 ... behind shutter 10 ... TW switching device 11 ... TW subset slider 12 ... first switching lever 13 ... second switching lever 14 ... … Switching cam 15 …… Motor 16 …… Motor switch 17 …… Motor switch lever 18 …… Latch set lever 20 …… Transmission switching mechanism 23 …… Swing restriction lever 25 …… Latch lever 26 …… Transmission lever 27 …… TW set slider 30 …… Release pin 46 …… TW switching knob.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tokuya Mochizuki 369 Nagata Mansion 306, Shimizu-cho, Showa-cho, Nakakoma-gun, Yamanashi Prefecture (72) Inventor Kazuo Kamata 2-26-30, Nishiazabu, Minato-ku, Tokyo Fuji Photo Film Co., Ltd. (56) References JP-A-62-144149 (JP, A) JP-A-60-88327 (JP, U)

Claims (2)

[Claims] 1. A focal length switching camera for selectively switching a shooting lens including a master lens and a conversion lens between a telephoto shooting position and a wide-angle shooting position by a motor, and biases the master lens toward the telephoto shooting position. Energizing means, a switching cam rotated by the motor, two stop portions for stopping rotation of the switching cam formed on the switching cam at unequal length intervals in the circumferential direction, and engaging with the stop portions. Stopping means for stopping the rotation of the switching cam, a pushing portion eccentrically provided on the switching cam, and the master lens are linked, and are biased by the biasing means to contact the pushing portion, It is equipped with a focal length switching lever that swings by the displacement of the pushing part due to the rotation of the switching cam and moves the master lens in the optical axis direction. Using the other rotation area, the pusher is brought into contact with the one closer to the mounting shaft of the switching lever to set the master lens to the telephoto shooting position, and at the same time the unequal length interval by the two stops is short. A focal length switching camera, characterized in that the master lens is set at a wide-angle photographing position by bringing the pushing portion into contact with a mounting shaft of a switching lever at a remote side by using one rotation region. 2. The stop portion is a notch formed on the peripheral surface of the switching cam, and the stop means has a motor switch lever arranged so that one end can enter and leave the notch, and the motor switch lever It turns off when it enters the notch, turns on when it comes out and comes into contact with the peripheral surface, and the motor switch that rotates the motor, and it enters the rotation range of the pushing part,
In addition, a latch set lever that is pushed to the latch position by the pusher during the rotation of the switching cam, a latch lever that locks the latch set lever when it moves to the latch position, and a focal length switching operation. It is hung between the wide-angle telephoto set lever that releases the lock of the latch lever by the and the latch set lever and the switch lever.When the latch lever is unlocked, the switch lever is attached so that it will come out of the notch. Momentum,
The focal length switch according to claim 1, characterized in that, when the latch set lever is latched by the latch lever, the switch lever comprises a spring for urging the switch lever in a direction to enter the notch of the switching cam. camera.