JPH0823657B2 - Focusing device for shooting optical system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an optical system between a position where a front lens of a photographing optical system projects forward from a camera body and a position retracted rearward from the position. The present invention relates to a focus adjustment device for a camera that adjusts the position of the optical system in the optical axis direction by moving the.

[Conventional technology]

As the above-described camera, there is conventionally known one in which a focal length switching mechanism is configured by a screw member extending in the optical axis direction and a base plate of a photographing optical system screwed to the screw member. In this structure, a screw member is driven and rotated by a motor or the like to move the photographing optical system on the base plate in the optical axis direction so that the focal length can be switched and the focal point can be adjusted at each focal length. (For example, JP-A-60
-122931).

[Problems to be solved by the invention]

However, the above-mentioned conventional configuration has the following problems.

In this type of camera, a member that holds the front lens when the front lens is in the protruding position, for example, the movable lens barrel largely protrudes from the camera body. Therefore, it is easy for external impact to be applied to this part that greatly protrudes from the camera body, especially when the camera is placed with the front lens side down.
The entire weight of the camera body is added to this protruding portion.

In the case of the above-described conventional configuration, the focal length switching mechanism is composed of a screw member extending in the optical axis direction and a base plate for supporting the front lens that is screwed into the screw member, and since both are always linked, As described above, when an impact or an external force is applied to a portion that largely projects from the camera body when the front lens is in the projecting position, it may directly affect the focal length switching mechanism and cause damage to the focal length switching mechanism. was there.

Further, if the operation of the member holding the front lens is obstructed from the front while the member holding the front lens is being driven in the protruding direction, damage may occur.

In view of the above situation, an object of the present invention is to prevent an unreasonable force from being applied by a shock, an external force, or the like when the front lens is in the protruding position.

[Means for solving problems]

The present invention relates to a camera for performing focus adjustment of an optical system by moving the optical system between a position where the front lens of the photographing optical system projects forward from the camera body and a position retracted rearward from the position. A biasing means for biasing the optical system in a direction projecting forward, and a pressing portion for pressing the optical system rearward against the biasing force of the biasing means. By changing the position, the position of the optical system in the direction of the optical axis is arbitrarily adjusted, and thereby the moving unit for adjusting the focus of the optical system, and the entire area of the pressing portion of the moving unit, the optical system is It is characterized in that a retreat allowance region is formed which is released from the pressing by the pressing portion and is movable rearward from the position adjusted by the pressing portion against the bias of the biasing means.

[Action]

In other words, when the front lens is in the protruding position, the member that holds the front lens is impacted or the camera is placed with the front lens side down, so that the weight of the camera body does not increase in the member that holds the front lens. Even if it is applied, since the optical system is released from the pressing by the pressing portion and the optical system is allowed to retreat against the bias of the biasing means, the force applied to the member holding the front lens is absorbed. Therefore, it is possible to avoid the damage due to the excessive force.

Also, even if the operation is blocked from the front while driving in the direction of projecting the front lens, it is allowed to separate from the pressing part and stop the feeding of the optical system. It is prevented from being damaged.

Then, when the external force disappears, the optical system returns to the original position determined by the pressing portion by the urging force of the urging means, so that the optical system returns to the original state, and shooting can be continued.

〔Example〕

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

The following embodiments will be described with reference to a bifocal switching camera which is an example of a focal length switching type camera that can selectively perform standard shooting and telephoto shooting. The present invention can also be applied to, for example, a three-focal point switching camera, which can do this by switching the focal lengths in multiple stages other than that.

FIG. 2 is a top view of the camera according to the present invention. (1) is a release button, and (2) is a focal length switching button as a switching operation tool for switching the focal length of the photographing optical system (PS) described later.

Each time the focal length switching button (2) is pressed,
The focal length of the shooting optical system (PS) is standard (for example, 50 mm)
The state (hereinafter, this state is referred to as the standard shooting state)
And a state that is longer than the standard (for example, 70 mm) (hereinafter,
This state is referred to as a telephoto shooting state) and is sequentially switched.

In addition, in place of this focal length switching button (2),
As shown in the figure, a slide type focal length switching lever (2 ') may be provided as a switching operation tool. In this configuration, setting the focal length switch lever (2 ') to the <TELE> position will switch to the telephoto shooting mode, and setting it to the <STND> position will switch to the standard shooting mode.
By setting it to the <OFF> position, the power supply to each part of this camera is stopped.

The photographic optical system (PS) is housed in the camera body (3) and a fixed lens barrel (3A) connected to the camera body (3), and a shutter block (described later) from the tip of the fixed lens barrel (3A). The tip of the main lens frame (4b) held in 4) is projected. As will be described later in detail, the main lens frame (4b) is located at the position shown by the broken line in the figure in the standard shooting state and at the position shown by the chain double-dashed line in the figure in the telephoto shooting state.

FIG. 1 shows the overall configuration of the photographing optical system (PS) and the founder optical system (FS).

In the figure, (4) is a shutter block, which is a main lens (4a) used for both standard shooting and telephoto shooting.
A main lens frame (4b) holding the main lens (4a) which is the front lens of the photographing optical system (PS) and a shutter (not shown) are integrally assembled. The shutter block (4) is slidably supported in the optical axis (L) direction by a pair of shafts (5X) and (5Y) fixedly mounted on the fixed base plate (5), and a spring ( By 6), it is biased to the front side.

The shutter block (4) is supported by a support lever (7A) that is rotatable around an axis (X ₁ ) parallel to the optical axis (L), and is inserted into the shooting optical path only in the telephoto shooting state. A secondary lens (7) is attached. Then, in a state of covering the sub-lens (7), the fixed base plate (5) integrally molded can be slidably fitted in the lower half portion (5A) which is the first cylindrical mounting frame. A movable lens barrel (8) is fixed to the shutter block (4), both are slidable in the optical axis (L) direction, and are biased forward by a spring (6).

As shown in FIGS. 3 (a), (b), and FIG.
The support lever (7A) for the sub lens (7) is urged by the spring (9) toward the side where the sub lens (7) is inserted into the photographing optical path. A gear portion (7a) is formed on the outer peripheral surface of the shaft core portion of the support lever (7A). Further, a fan-shaped operation member (11) that integrally rotates around the same axis (X ₂ ) as the gear member (10) having a gear portion (10a) that meshes with the gear portion (7a) is provided.

As shown in FIGS. 5 and 6, the operating member (11)
Has an oval-shaped section (11a) having an oval cross section. The shaft-shaped section (11a) is inserted into the round hole (10b) of the gear member (10) so as to be relatively rotatable, and further, the intermediate member ( 12) Oval hole (12
It is fitted in a) so that it cannot rotate relative to it. Then, as shown in FIGS. 5 and 7, the arm portion (12
b) and the arm portion (10b) of the gear member (10) are overlapped with each other, and a coil spring (13) having both ends bent so as to sandwich them is provided.

As shown in FIG. 4, with the operating member (11) rotated clockwise, the intermediate member (12) and this intermediate member (1
The gear member (10), which is interlocked with the spring in 2), is in the position rotated in the same direction. The support lever (7A) is counterclockwise against the biasing force of the spring (9) due to the engagement between the gear portion (10a) of the gear member (10) and the gear portion (7a) of the support lever (7A). And the auxiliary lens (7) is retracted from the shooting optical path.

At this time, the operation member (11) which is the operation side member is spring-connected to the gear member (10) which is the operated side member which is gear-connected to the support lever (7A) of the sub-lens (7). By doing so, relative rotation is possible, and even after the holder (7B) of the sub-lens (7) contacts the upper frame (8a) of the movable lens barrel (8), the sub-lens (7) can be retracted. Since the sub lens (7) is retracted from the photographing optical path, the operation amount of the operation member (11) can be set to a large amount while the sub lens (7) retreats from the photographing optical path. The sub-lens (7) can always be surely retracted from the photographing optical path regardless of manufacturing errors and mounting errors of the components that make up the mechanism.

As shown in FIGS. 5 and 10, this operation member (11)
Is exposed to the outside from the upper surface of the movable lens barrel (8). Then, as shown in FIGS. 8 and 10, as the shutter block (4) moves in the direction of the optical axis (L), it comes into contact with the operating projection (11b) of the operating member (11). Cam surface (5a) for retracting the secondary lens (7) from the shooting optical path
Are integrally connected to the inside of the fixed base plate (5).

In the standard photographing state, as shown in FIG. 3 (a), FIG. 9 (a), and FIG. 10, the operation table (11b) of the operation member (11) is fixed to the fixing base plate (5). The flat portion (5x) of the cam surface (5a) is in contact. At this time, the operating member (1
1) is held in the most clockwise position around the axis (X ₂ ), and the sub-lens (7) is at a position retracted from the photographing optical path against the biasing force of the spring (9).

The flat portion (5x) of the cam surface (5a) is formed in parallel with the optical axis (L) and has a certain length. That is, in the standard photographing state, when the movable lens barrel (8) is moved back and forth in the optical axis (L) direction together with the shutter block (4) to perform the focus adjustment operation as described later, the sub lens (7) is used. It is configured to be kept retired from the photographing optical path.

The cam surface (5a) has an optical axis (L) following the flat part (5x).
It has a curved portion (5y) that is curved away from the. The shutter block (4) and the movable lens barrel (8) are both moved forward along the optical axis (L) from the above-described standard photographing state, so that the spring (9) causes the shutter block (4) and the movable lens barrel (8) to move as shown in FIG. , (B), and the operation projection of the operation member (11) that is urged to rotate in the counterclockwise direction in the drawing in conjunction with the support lever (7A) that is urged to rotate in the clockwise direction in FIG. (11
As shown in FIG. 9 (b), b) comes out of contact with the flat portion (5x) of the cam surface (5a) and comes into contact with the curved portion (5y).

As a result, the support lever (7A) is rotated clockwise by the urging force of the spring (9), the sub-lens (7) is inserted into the photographing optical path, and the pin (4b) is implanted in the shutter block (4). A) and positioned. This allows
The telephoto shooting state appears. This state is shown in FIG. 3 (b) and FIG. 9 (c).

At this time, the operation protrusion (11b) of the operation member (11) is
After detaching from the cam surface (5a) of the fixed base plate (5), the shutter block (4) and the movable lens barrel (8) are moved back and forth in the optical axis (L) direction in order to perform a focus adjustment operation as described later. To contact the cam surface (5a). That is, in the telephoto shooting state, the sub-lens (7) is kept inserted in the shooting optical path.

That is, the support lever (7A) of the sub lens (7), the spring (9), the pin (4b) of the shutter block (4), the gear member (10), the intermediate member (12), the operating member (11), the coil spring. (13), the upper frame (8a) of the movable lens barrel (8), and the cam surface (5a) of the fixed base plate (5) change the position of the sub lens (7) between the projecting position and the retracted position. It constitutes a fixed access means.

Returning to FIG. 1 and continuing the description, a motor (M) is incorporated in the side portion of the fixed base plate (5). Further, a gear base plate (23) is provided below the lower half portion (5A) of the fixed base plate (5) and is screwed to the fixed base plate (5).

On the gear base plate (23), a payout cam (14) rotatable around an axis (X ₅ ) and a rotational driving force transmitted from the motor (M) to the rotary payout cam (14). Gear train (15),
A stop lever (16) having a pawl (16a) that engages with a ratchet portion (14a) on the outer peripheral surface of the feeding cam (14), and a magnet (1 that controls the operation of the stop lever (16).
7) and the taking optical system (P
The drive mechanism for the photographic optical system (PS), which is composed of the feeding lever (18) that is the cam follower on the (S) side, is mounted.

The stop lever (16) is attached rotatably around the shaft center (X ₃ ), and the stop lever (16) is counterclockwise in FIG. 1, that is, the claw (16
A spring (19) is provided which biases a) in a direction in which the ratchet portion (14a) of the feeding cam (14) is engaged. Also, the stop lever (16), the end opposite to the claw (16a) to the mounting axis (X _3), the magnet (1
An iron piece (20) that is adsorbed on 7) is attached.

Then, activate this magnet (17) to move the iron piece (2
By adsorbing (0), the pawl (16) of the stop lever (16)
a) and the ratchet portion (14a) of the feeding cam (14) are disengaged to allow rotation of the feeding cam (14), while stopping the operation of the magnet (17), the spring (15) ), The stop lever (16) is rotated counterclockwise, and its pawl (16a) is engaged with the ratchet portion (14a) of the feeding cam (14) to prohibit rotation of the feeding cam (14). It is configured to be able to.

Further, as shown in FIG. 11, the feeding lever (18) has
On its lower surface, a first pin (18a) pivotally supported by a pivotal support portion (21a) of a support lever (21) attached to a gear base plate (23).
In addition, two pins (hereinafter referred to as a second pin and a third pin, respectively) (18b) and (18c) are implanted. In addition, the fourth pin (18) is attached to the upper surface of the feeding lever (18) which is rotatable around the axis (X ₁ ) with the first pin (18a) as a fulcrum.
d) is planted.

The second pin (18b) and the third pin (18c) are respectively
A pair of cam surfaces (hereinafter referred to as a first cam surface and a second cam surface) formed on the inner circumference of the operation cam (14) (14b), (14
It is configured so as to individually abut on c). The fourth pin (18d) engages with an elongated hole (not shown in FIG. 2) (8a) formed in the lower surface of the movable lens barrel (8) and extending in a direction orthogonal to the optical axis (L). I am fit.

In other words, this feeding lever (18) has its second pin (18
b) Alternatively, the third pin (18c) is brought into contact with the pair of cam surfaces (14b), (14c) of the feeding cam (14) and maintained in a predetermined posture, thereby holding the photographing optical system (PS). The fourth pin (18d) that engages with the movable lens barrel (8) that is a frame regulates the movement of the shutter block (4) biased forward by the spring (6) and positions it. It is configured. The operation will be described later.

Then, as described above, in the telephoto shooting state, the main lens frame (4b) holding the main lens (4a) which is the front lens of the shooting optical system (PS) attached to the shutter block (4) is As shown by the chain double-dashed line in FIG. 2, it is in a projecting position projecting from the camera body (3). In this state, as described above, the shutter block (4) is positioned together with the main lens (4a). A spring (6) that biases the shutter block (4) forward, and a mechanism that slides the main lens (4a) to the retracted position side against the biasing force of the spring (6), that is, a motor (M). ,
Gear train (15), feeding cam (14), and feeding lever (1
8) It is carried out by the operation mechanism linked with.

Then, as shown in FIG. 11, a pair of cams of the feeding cam (14) are provided between the feeding cam (14) which is the operating side member of this operating mechanism and the feeding lever (18) which is the operated side member. When the pair of pins (18b) and (18c) of the feeding lever (18) corresponding to the surfaces (14b) and (14c) come into contact with each other in a one-sided contact, the feeding lever (18) swings toward the retracted position. Since it is allowed, if external force is applied to the shutter block (4) that holds the main lens (4a) in the telephoto shooting state, for example, this camera is placed with the shutter block (4) facing down. Swing lever (18)
Since it swings away from the feeding cam (14), it is possible to prevent external force from being absorbed by the spring (6) and to apply an unreasonable force to the operating mechanism, and to reduce the damage.

As will be described in detail later in the description of the operation, the feeding cam (14) is rotated in a predetermined both forward and backward directions by the forward and reverse rotation of the motor (M) described above, and the feeding lever (18) is moved in response to the change in posture. By positioning the shutter block (4) through the lens barrel (8), the main lens (4a) can be moved along the optical axis (L) direction and the sub lens (7) can be moved in and out of the shooting optical path. Be seen.

Then, by driving the motor (M), the focal length is switched between the standard photographing state and the telephoto photographing state, and further, in each of these two photographing states, the main lens (4a) is driven by the same motor (M) driving. ) Is moved so that the focus adjustment operation can be performed.

That is, by the gear train (15), the feeding cam (14), the feeding lever (18), the stop lever (16), the magnet (17), the motor (M), etc., the focal length of the photographing optical system (PS) The operation means is configured to sequentially perform switching and focus adjustment at each focal length by a series of operations.

At this time, the shutter block (4) is biased to the front side, and the positioning thereof is brought into contact with the pair of cam surfaces (14b) and (14c) of the feeding cam (14).
b) and (18c), the feeding lever (18) is used to rotate the feeding cam (14) at a constant speed, but the tangential direction of the rotation locus of the feeding cam (14), that is, this cam (14). The inclination angle of the cam surfaces (14b), (14c) with respect to the operation direction of the shutter block (4) is determined by the required moving speed of the shutter block (4) (for example, during the focus adjustment operation in the telephoto shooting condition, It can be formed to match the relative moving speed, such as faster, or faster than the focus adjustment operation during the focal length switching operation, so the focal length switching operation during shooting can be performed quickly. ,And,
The focus adjustment operation can be performed with high accuracy.

The first cam surface (14b) of the feeding cam (14) and the second pin (18b) of the operation lever (18) contacting the first cam surface (14b) are used for the focus adjustment in the standard photographing state of the photographing optical system (PS) and the standard photographing. The first half of the switching of the focal length from the state to the telephoto state is performed.

In addition, the second cam surface (14c) of the feeding cam (14) and the third pin (18c) of the operation lever (18) contacting the second cam surface (14c) are the focal lengths of the photographing optical system (PS) from the standard photographing state to the telephoto photographing state. The focus adjustment is performed in the latter half of the switching of, and in the telephoto shooting state.

That is, the first cam surface (14b) of the feeding cam (14) has one end of the short focal length side focus adjusting cam surface (14X) and the focal length switching cam surface (14Y), and the second cam surface. The other end of the focal length switching cam surface (14Y) and the long focal length side focus adjusting cam surface (14Z) are formed on the surface (14c).

Then, these short focal length side focus adjustment cam surfaces (14
X), the focal length switching cam surface (14Y), and the long focal length side focus adjusting cam surface (14Z), in that order, the rotation direction of the rotary feeding cam (14), that is, this cam (14). Are formed side by side in the operating direction of.

In this way, by dividing the cam surface into the first cam surface (14b) and the second cam surface (14c), it is possible to reduce the operation error of the feeding lever (18) which is the cam follower.

That is, if the cam surface is a series, one end of the cam surface is formed near the rotation axis (X ₅ ) of the feeding cam (14). In that case, the circumferential length of the cam surface relative to the constant rotation angle of the feeding cam (14) becomes relatively short. Then, the cam surface formed near the rotation axis (X ₅ ) of the feeding cam (14) has the same rotation angle error as the cam surface formed near the outer peripheral surface of the feeding cam (14). The error in the circumferential direction is large, and the operating error of the feeding lever (18), which is the cam follower, is accordingly large.

On the other hand, by dividing the cam surface as described above and changing the cam surface during the operation, the cam surface can be formed only near the outer peripheral surface of the feeding cam (14), and an operation error is also caused. It can be made smaller.

Furthermore, the first cam surface (14b) and the second cam surface (14c), which are the divided peripheral surfaces of the rotary feeding cam (14), are the depth from the uppermost surface of the feeding cam (14), that is, the feeding surface. The position of the cam (14) in the direction of the rotation axis (X ₅ ) is different. Corresponding to this, a pair of pins (18b) and (18c), which are cam followers provided on the feeding lever (18) that is a cam follower, respectively corresponding to the pair of divided peripheral surfaces (14b) and (14c).
Is the operating lever (18) as shown in Figs. 11 and 12.
The amount of protrusion from the base plate (18A) of is different.

That is, in this manner, the cam surfaces (14b) and (14c) of the rotary feeding cam (14) are divided, and the two-stage structure in which the feeding cam (14) is displaced in the rotation axis (X ₅ ) direction By configuring as above, the cam surfaces (14b) and (14c) can be configured to have a large displacement width in the radial direction of the feeding cam (14), and therefore the shutter block (4) Both of these cam surfaces (14
b) and (14c) can have a large rotation angle with respect to the rotary shaft center (X ₅ ) of the feeding cam (14) compared to the linear movement amount of the shutter block (4), thus reducing the operation error. Can be measured.

Further, the pair of cam surfaces (14b), (1
4c), the focus adjustment cam surface (14X), (14Z)
As shown in FIG. 13, in each case, several cylindrical surfaces (m) with different distances from the rotation center (X ₅ ) of the feeding cam (14) are placed between each cylindrical surface (m). It is configured to be connected by the extending inclined surface (n).

Then, the inclined surface (n) is an operation area where focus is adjusted by operating the operation lever (18) which is a cam follower, and the cylindrical surface (m) is a non-operation area. The fourth pin (18d) of the operation lever (18) serves as a focus adjusting member of the photographing optical system (PS).

Next, the cylindrical surface (m) and the inclined surface (n) of the focus adjusting cam surfaces (14X) and (14Z) will be described.

All of the pair of cam surfaces (14b) and (14c) are linearly expanded as shown in FIG. Note that the drawing shows a developed view of only the first cam surface (14b), and the following description will be made accordingly. That is, some cylindrical surfaces (m) correspond to straight line portions (m ′) extending in the left-right direction in the figure, and inclined surfaces (n) connecting these some cylindrical surfaces (m) to each other are straight line portions. (M ') Corresponds to the inclined portion (n') extending between them.

The second pin (18b) of the feeding lever (18) corresponding to the first cam surface (14b) is located in any of the longitudinal directions of the linear portion (m ') as shown in FIG. It is configured to come into contact with that portion (actually, any portion in the circumferential direction of the cylindrical surface (m)).

Even if the second pin (18b) of the feeding lever (18) is at any position shown by the solid line, the one-dot chain line and the two-dot chain line in FIG. 14, the posture of the feeding lever (18) does not change and the shutter block The positions of (4) and the movable lens barrel (8) in the optical axis (L) direction do not change. That is, when positioning the shutter block (4) and the movable lens barrel (8) in the optical axis (L) direction, there is a margin in the circumferential direction at the rotation stop position of the feeding cam (14). This has the following implications.

That is, in the focus adjustment operation, when stopping the movement of the shutter block (4) in the optical axis (L) direction, the drive of the motor (M) is stopped to stop the rotation of the feeding cam (14) and the magnet ( 17) Stop the operation and pull out the pawl (16a) of the stop lever (16) to feed the cam (14).
It is configured to be engaged with the ratchet part (14a).

At this time, when the battery as the power source is new and the power source voltage is sufficiently high, the driving force of the motor (M) is sufficient. Therefore, after the motor (M) is stopped, the feeding cam (14) is rotated by a predetermined amount. , The claw (16a) of the stop lever (16) fully enters the ratchet part (14a) of the feeding cam (14). Then, the second pin (18b) of the feeding lever (18) is at the position shown by the solid line in FIG. 14 at the first cam surface (14b) of the feeding cam (14).
The feeding cam (14) is positioned so as to come into contact with.

On the other hand, when the battery becomes old and the power supply voltage drops, the driving force of the motor (M) is insufficient and the rotation amount of the feeding cam (14) after the motor (M) is stopped is a predetermined amount. The situation may fall below. In this case, the feeding cam (14) is positioned without the pawl (16a) of the stop lever (16) sufficiently entering the ratchet portion (14a) of the feeding cam (14). The second pin (18b) of the feeding lever (18) is located at the position indicated by the one-dot chain line or two-dot chain line in FIG. 14 and is located at the first cam surface (14) of the feeding cam (14).
Contact b).

As described above, the second pin (18b) of the operation lever (18) in FIG. 14 is connected to the first cam surface (14b) of the feeding cam (14).
The positions of the shutter block (4) and the movable lens barrel (8) in the direction of the optical axis (L) do not change as long as they abut the same straight line portion (m ′). Therefore, as described above, even if the stop position of the feeding cam (14) slightly varies due to fluctuations in the power supply voltage or the like, stable positioning of the main lens (4a) is always performed. .

Although not shown, the third pin (18c) of the feeding lever (18) and the second cam surface (14c) of the feeding cam (14) have the same configuration.

On the other hand, the support lever (21), which is a support member for rotatably supporting the feeding lever (18) by pivotally supporting the first pin (18a) of the feeding lever (18) on the pivot portion (21a), As shown in FIG. 15 and FIG. 15, it is fitted onto a pin (23i) planted in the gear base plate (23) and is rotatably attached around a shaft core (X ₆ ).

The support lever (21) has a long hole (21b) formed on the side opposite to the pivotal support (21a) with the pivot axis (X ₆ ) interposed therebetween, while the gear lever plate (23) has a long hole (21b). A hole (23j) having a diameter equal to or larger than the minor axis of the long hole (21b) is formed at a position corresponding to the long hole (21b).

The support lever (21) can be fitted into the long hole (21b) of the support lever (21) at the tip of the first cylindrical shaft having the same outer diameter as the inner diameter of the hole (23j) of the gear base plate (23). A jig (not shown) provided with an eccentric second cylindrical shaft having a large outer diameter is inserted into the hole (23j) of the gear base plate (23) from below to make only the second cylindrical shaft long. By being inserted into the hole (21b) and rotated, it is configured to rotate around the shaft core (X ₆ ).
In the figure, (22) is a fixing screw, the threaded portion of which penetrates another elongated hole (21c) formed in the support lever (21) and is screwed to the gear base plate (23).

That is, the support lever (21) is rotatably attached around the axis (X ₆ ), and the operation lever, which is a cam follower, is provided by the position change operation elongated hole (21b) and the fixing screw (22). An adjusting means for changing the position of the support lever (21) which is a support member of (18) is configured.

By rotating the support lever (21) around the axis (X ₆ ), the position of the pivotal support (21a) also moves. For example, the first
5 From the state shown by the solid line in the figure, turn the support lever (2
When 1) is rotated, as shown by the chain double-dashed line in Fig. 15,
The pivot part (21a) moves downward in the figure.

At this time, the feeding lever (18) has its fourth pin (18
The second pin (18b) is positioned by contacting the first cam surface (14b) of the feeding cam (14) with the second pin (18b) engaged with the movable lens barrel (8). Rotate counterclockwise around (18b) as a fulcrum. Therefore, as shown by the chain double-dashed line in FIG. 15, the fourth pin (18d) of the feeding lever (18)
Moves upward in the figure.

As a result, the shutter block (4) and the movable lens barrel (8) biased to the front side in the optical axis (L) direction move to the front side and the position of the main lens (4a) changes.

In FIG. 15, the first pin (18
b) is located at the starting end portion (14s) of the first cam surface (14b) of the feeding cam (14). As will be described later, this position corresponds to a state in which the photographing optical system (PS) (in this case, the main lens (4a)) is in focus at the infinite position in the standard photographing state. At this time, if there is no error, the lens block (4) and the movable lens barrel (8) are at the rear end edge of the moving range.

As described above, by rotating the support lever (21) to change the position of the main lens (4a), the feeding lever is irrespective of errors due to manufacturing errors and assembly errors of the main lens (4a). With the first pin (18b) of (18) positioned at the starting end (14s) of the first cam surface (14b) of the feeding cam (14), the photographic optical system (PS) should be focused to the infinity position. In addition, it is configured so that the position of the photographing optical system (PS) can be finely adjusted.

The elongated hole (21b) for position changing operation, which is an adjusting portion constituting the adjusting means, faces the outside of the above-mentioned operating means. Therefore, the fine adjustment of the position of the photographing optical system (PS) described above can be easily performed even after the operation means is assembled.

It should be noted that in FIG. 15, the rotation of the support lever (21) occurs when the first pin (18b) of the feeding lever (18) is in contact with the first cam surface (14b) of the feeding cam (14). Although the fine adjustment of the photographing optical system (PS) is shown, it is finely adjusted when the second pin (18c) of the feeding lever (18) is in contact with the end portion of the second cam surface (14c) of the feeding cam (14). Adjustments may be made. This position corresponds to a state in which the taking optical system (PS) (in this case, the main lens (4a) and the sub lens (7)) is focused on the closest position in the telephoto shooting state, and if there is no error, The shutter block (4) and the movable lens barrel (8) are located at the foremost edge of the moving range.

On the other hand, on the lower surface of the feeding cam (14), three position detecting brushes (hereinafter, referred to as a first brush, a second brush and a third brush) are provided with different positions in the circumferential direction, as shown in FIG. (14A), (14B), and (14C). Further, as shown in FIG. 17, on the upper surface of the gear base plate (23) which is a fixed part on which the feeding cam (14) is mounted, as shown in FIG. 17, three position detecting screw brushes (of the feeding cam (14) ( 14
A), (14B), (14C) are appropriately contacted to form a sensor for detecting the cam position, which will be described later.
A position detection pattern for electrically opening and closing (S5) according to the rotational position of the feeding cam (14) is formed.

This position detection pattern is the center of rotation of the feeding cam (X ₅ )
5 circular arc terminals (23A) with approximately concentric circles centered on
(23E).

The innermost circular arc terminal (23A) and the fourth circular arc terminal (23D) from the innermost circumference together with the second brush (14B) together with the photographing optical system in two photographing states of a standard photographing state and a telephoto photographing state ( The lens initial state detection switch (S3) for detecting the initial state of PS) (the state of focusing on the infinity position in this embodiment) is configured. Then, when the shooting optical system (PS) is in the initial state, the second brush (14B)
One end of the non-conducting part (23x), which is separated from the arc terminal (23D),
Contact the (23y), lens initial state detection switch (S3)
Are configured to be closed.

In addition, the third arc (23C) from the innermost circumference and the protruding parts of the fourth and fifth arc terminals (23D) and (23E) from the innermost circumference together with the third brush (14C) are standard images. A lens position detection switch (S4) for detecting the amount of movement of the shutter block (4) in two shooting states, that is, a shooting state and a telephoto shooting state, is configured. The lens position detection switch (S4) repeatedly opens and closes according to the rotation of the feeding cam (14) for moving the shutter block (4) and outputs a pulse signal. Then, the control device (24) described later is configured to count the pulse signal and detect the position of the shutter block (4).

Furthermore, the second arc terminal (23B) from the innermost circumference and the outermost arc terminal (23E), together with the first brush (14A), indicate whether the shooting optical system (PS) is in the standard shooting state or the telephoto shooting state. The lens area detection switch (S5) for detecting which of the two states is included. When the photographing optical system (PS) is in the telephoto photographing state, that is, the shutter block (4) is located on the front side of the optical axis (L) and the sub lens (7) is inserted in the photographing optical path. While it is in contact, one end of the first brush (14A) abuts the non-conducting portion (23z) which is separated from the arc terminal (23B), and the lens area detection switch (S
5) is configured to be closed.

Then, as shown in FIG. 18, on the bottom surface of the gear base plate (23), a group of connecting terminals (23) connected to the respective arc terminals (23A) to (23E) through through holes, respectively.
a) to (23e) are exposed from the gear base plate (23) to the outside.

As shown in FIG. 19, the control device (24) includes a release switch (S1) which is opened / closed in conjunction with the operation of the release button (1) in addition to the above-mentioned three switches (S3) to (S5). A lens selector switch (S2) that is opened / closed in conjunction with the operation of the focal length selector lever (2) for selecting the standard photographing state and the telephoto photographing state is connected.

Further, the control device (24) includes a motor (M) for moving the shutter block (4) and the movable lens barrel (8) in the optical axis (L) direction, and rotation of the feeding cam (14). A magnet (17) for controlling the operation of a stop lever (16) for prohibiting and allowing is connected. And
Control signals are output to the motor (M) and the magnet (17) according to the states of the switches (S1) to (S5) described above.

Next, this control and the accompanying focal length switching operation and focus adjusting operation will be described with reference to FIGS. 20 (a) to 20 (e) and the flowcharts of FIGS. 21 and 22.

<< 1 >> Focus adjustment operation in standard shooting state The state shown in Fig. 20 (a) is the initial state of standard shooting state, that is, the shooting optical system (PS) (consisting only of the main lens (4a)) is infinite. It is in a state of being focused on a distant position. At this time, the shutter block (4) is in a state of stopping the main lens frame (4b) at the position shown by the broken line in FIG. 2, and the main lens (4a) which is the front lens incorporated in this shutter block (4). ) Is also in the retired position.

In this state, the claw (16a) of the stop lever (16)
The feeding cam (14) is in contact with a portion of the outer peripheral surface other than the ratchet portion (14a). The iron piece (20) is in contact with the magnet (17).

Then, the second pin (18b) of the feeding lever (18) is in contact with the starting end portion (14s) of the first cam surface (14b) of the feeding cam (14), whereby the front side in the optical axis (L) direction. The shutter block (4) biased to the side (upper side in the drawing) is positioned. In addition, the third pin (18
c) is not in contact with the second cam surface (14c) of the feeding cam (14).

At this time, only the lens initial state detection switch (S3) is closed, and the other switches (S1), (S2), (S
3), (S4) and (S5) remain open (see <# 0> in Fig. 21, only step number is shown below.) Release button (1) is operated to release button (S1)
Is closed <# 1>, the magnet (17) is activated to attract the iron piece (20) <# 2>, and the motor (M) starts rotating counterclockwise in FIG. 20 (a). <# 3>.
Then, the feeding cam (14) starts rotating clockwise in the drawing through the gear train (15), and the lens initial state detection switch (S
3) is released <# 4>.

With the rotation of the feeding cam (14), the second pin (18b) of the feeding lever (18) causes the first cam surface (14b) of the feeding cam (14).
And the feeding lever (18) rotates counterclockwise around the axis (X ₄ ). As a result, the shutter block (4) is moved forward by the urging force of the spring (6) in the optical axis (L) direction.

The lens position detection switch (S4) is repeatedly opened and closed according to the rotation of the feeding cam (14) <# 5,6>, and when the photographing optical system (PS) reaches the in-focus position, the motor (M) is rotated. The rotation is stopped <# 7>. To determine whether the shooting optical system (PS) has reached the in-focus position <# 6>, the pulse signal output by opening and closing the lens position detection switch (S4) is counted within the control position (24). The count value is compared with the separately obtained focus count value.

After short-circuiting both ends of the motor (M) to stop its rotation <# 7>, the power to the magnet (17) is cut off <# 8>. As a result, the stop lever (16) is urged by the spring (19), as shown in FIG.
It rotates counterclockwise around the axis (X ₃ ), and its pawl (16a) engages with the ratchet portion (14a) of the feeding cam (14) to position the feeding cam (14).

Then, start a timer (not shown) <#
9>. After that, the shutter (not shown) is opened and closed <# 10>, and the timer waits until the time is up <# 1
1>. This timer is set to expire after a time slightly longer than the maximum shutter speed. That is, in step <# 11>, the shutter opening / closing operation is completed.

When the opening / closing operation of the shutter is completed, the motor (M) starts rotating clockwise in Fig. 20 (B) <# 1
2>. Then, the feeding cam (14) starts rotating counterclockwise in the figure via the gear train (15). Along with this, the feeding lever (18) rotates clockwise, and the shutter block (4) and the movable lens barrel (8) are fed rearward in the optical axis (L) direction.

When the feeding cam (14) reaches the initial position, the lens initial state detection switch (S3) is closed <# 13>. After that, both ends of the motor (M) are short-circuited to stop its rotation <# 14>, and the power to the magnet (17) is cut off <#
15>.

As a result, the initial state shown in FIG. 20 (a) is restored <# 16>.

<<2> Focal length switching operation Switching of the photographing state by the two focal lengths is performed by operating the focal length switching button (2). Each will be described below.

i) Switching from the standard shooting state to the telephoto shooting state In the initial state of the standard shooting state shown in Fig. 20 (a) (see <# 100> in Fig. 22, only the step number is shown below), the focal length switch button When the lens changeover switch (S2) is closed in conjunction with the pressing of (2) <# 101>, the state of the lens area detection switch (S5) is checked <# 102>. In the standard shooting state, this lens area detection switch (S5) is open, so <# 110>
Go to step.

First, the motor (M) rotates counterclockwise in FIG. 20 (a) <# 110>, and the magnet (17) is activated to attract the iron piece (20) <# 111>. The payout cam (14) starts rotating clockwise in synchronization with the rotation of the motor (M),
Lens initial state detection switch (S3) is opened <# 11
2>.

With the clockwise rotation of the feeding cam (14), as in the case of the focus adjustment operation in the standard photographing state, the feeding lever in which the second pin (18b) contacts the first cam surface (14b) of the feeding lever. (18) is rotated counterclockwise. This allows
The shutter block (4) and the movable lens barrel (8) are extended forward in the optical axis (L) direction.

The first cam surface (14b) of the feeding cam (14) does not extend over the entire circumference, and as shown in FIG.
8) rotates and its second pin (18b) moves to the first cam surface (14b).
When it goes beyond the end portion (14t) of b), it does not come into contact with the second pin (18b). Therefore, the delivery lever (18) is allowed to rotate further in the counterclockwise direction by being pulled by the shutter block (4) biased to the front side in the optical axis (L) direction.

At this time, the third pin (18c) of the feeding lever (18) is in contact with the second cam surface (14c) of the feeding cam (14), and thereafter, as the feeding cam (14) rotates in the clockwise direction. The rotation of the feeding lever (18) is controlled by the movement of the third pin (18c) of the feeding lever (18) along the second cam surface (14c).

When the lens area detection switch (S5) is closed by rotating the feeding cam (14) to a position corresponding to the telephoto shooting area of the shooting optical system (PS) <# 113>, the magnet (17) To the stop lever (1
This enables engagement of the feeding cam (14) with the ratchet portion (14a) by the claw (16a) of 6).

Further, if the lens initial state detection switch (S3) is closed <# 115>, both ends of the motor (M) are short-circuited to stop the rotation <# 116>. This state is the initial state of the telephoto shooting state shown in FIG.
0>. At this time, the shutter block (4) is at the position shown by the chain double-dashed line in FIG. 2, and the main lens (4a) that is the front lens
The main lens frame (4b) that holds the lens is located at a protruding position where it projects from the camera body (3).

As described above, the auxiliary lens (7) is inserted into the photographing optical path in accordance with this switching.

ii) Switching from the telephoto shooting state to the standard shooting state The initial state of the telephoto shooting state shown in Fig. 20 (d) <# 10
Similarly, in <0>, when the lens switch (S2) is closed <# 101>, it is in the telephoto state and the lens area detection switch (S5) is closed.
Judgment in step #, proceed to step <# 120>.

First, the motor (M) rotates clockwise in FIG. 20 (d) <# 120>. The feeding cam (14) starts rotating counterclockwise in association with the rotation of the motor (M), and the lens initial state detection switch (S3) and the lens area detection switch (S5) are opened one after another. # 121,122>.

With the rotation of the feeding cam (14) in the counterclockwise direction, the feeding lever (18) in which the third pin (18c) contacts the second cam surface (14c) thereof is rotated in the clockwise direction. As a result, the shutter block (4) and the movable lens barrel (8) are aligned with the optical axis (L).
It is pulled backward in the direction.

During the counterclockwise rotation of the feeding cam (14),
As shown in the figure (c), the third pin (18c) of the feeding lever (18) separates from the second cam surface (14c) of the feeding cam (14) and the second pin (18c) of the feeding lever (18). Is brought into contact with the first cam surface (14b) of the feeding cam (14), thereafter, the feeding lever is moved along the first cam surface (14b) as the feeding cam (14) rotates counterclockwise. The rotation of the feeding lever (18) is controlled by the movement of the second pin (18b) of (18).

If the lens initial state detection switch (S3) is closed by rotating the feeding cam (14) to a position corresponding to the infinity position of the standard shooting area of the shooting optical system (PS), then <# 12
3>, short-circuit both ends of the motor (M) to stop its rotation <# 124>. This restores the initial state of the standard shooting state shown in FIG. 20 (a) <# 130>.

During this switching, the magnet (17) is not energized, and the stop lever (16) is rotated in the direction in which its pawl (16a) engages with the ratchet portion (14a) of the feeding cam (14). However, there is no problem because the rotation direction of the feeding cam (14) is the counterclockwise direction, and the rotation is not prohibited by the engagement between the claw (16a) and the ratchet portion (14a). However, instead of this configuration, the magnet (17) may be actuated during the switching to separate the pawl (16a) from the ratchet portion (14a) to avoid generation of noise during rotation.

As described above, the sub-lens (7) is retracted from the photographing optical path in accordance with this switching.

In summary, the image is taken from the motor (M), the gear train (15), the feeding cam (14), the feeding lever (18), the shutter block (4), and the movable lens barrel (8) fixed to it. It constitutes a focal length switching mechanism that switches the focal length of the optical system (PS).

When a focal length switching lever (2 ') is provided instead of the focal length switching button (2), every time the lever (2') is moved between the <STND> and <TELE> positions. The lens selector switch (S2) may be configured to be closed.

<3> Focusing operation in telephoto shooting state In the initial state of the telephoto shooting state shown in FIG. 20 (d), the shooting optical system (PS) (consisting of the main lens (4a) and the sub lens (7)) Is focused at infinity.

In this state, the claw (16a) of the stop lever (16)
The feeding cam (14) is in contact with a portion of the outer peripheral surface other than the ratchet portion (14a). The iron piece (20) is in contact with the magnet (17).

The third pin (18c) of the feeding lever (18) is in contact with the second cam surface (14c) of the feeding cam (14), whereby the front side in the optical axis (L) direction (upper side in the figure). The shutter block (4) biased to is positioned. The second pin (18b) of the feeding lever (18) is not in contact with the first cam surface (14b) of the feeding cam (14).

At this time, the lens initial state detection switch (S3) and the lens area detection switch (S5) are closed, and the other switches (S1), (S2), (S4) remain open (Fig. 21). See <# 0>, only step number will be described below).

Operate the release button (1) to release the release switch (S
When 1) is closed <# 1>, the magnet (17) is activated to adsorb the iron piece (20) <# 2>, and the motor (M) moves to the first position.
Start rotation counterclockwise in Fig. 20 (a).
3>. Then, the feeding cam (14) starts rotating clockwise in the drawing through the gear train (15), and the lens initial state detection switch (S3) is opened <# 4>.

With the rotation of the feeding cam (14), the third pin (18c) of the feeding lever (18) causes the second cam surface (14c) of the feeding cam (14).
And the feeding lever (18) rotates around the shaft center (X ₄ ). As a result, the shutter block (4) is moved forward by the urging force of the spring (6) in the optical axis (L) direction.

The lens position detection switch (S4) is repeatedly opened and closed according to the rotation of the feeding cam (14) <# 5,6>, and when the photographing optical system (PS) reaches the in-focus position, the motor (M) is rotated. After shorting both ends to stop the rotation <# 7>,
Turn off the power to the magnet (17) <# 8>.

As a result, the stop lever (16) is moved by the urging force of the spring (19) as shown in FIG.
₃ ) It rotates counterclockwise around and its pawl (16a) engages with the ratchet part (14a) of the payout cam (14) and the payout cam (1
Position 4).

Then, start the timer <# 9>, open and close the shutter <# 10>, and wait until the end <# 9>
11>. When the opening / closing operation of the shutter is completed, the motor (M) starts rotating clockwise in Fig. 20 (e) <# 12>. Then, the feeding cam (14) starts rotating counterclockwise in the figure via the gear train (15). Along with that, the feeding lever (18) is rotated clockwise, and the shutter block (4) and the movable lens barrel (8) are fed rearward in the optical axis (L) direction.

When the feeding cam (14) reaches the initial position, the lens initial state detection switch (S3) is closed <# 13>. After that, both ends of the motor (M) are short-circuited to stop its rotation <# 14>, and the power to the magnet (17) is cut off <#
15>.

As a result, the initial state shown in FIG. 20 (d) is restored <# 16>.

On the other hand, when switching between the standard shooting state and the telephoto shooting state in the shooting optical system (PS) described above, the magnification is also switched in the viewfinder optical system (FS). Next, a configuration for that purpose will be described.

The viewfinder optical system (FS) includes an objective lens (25) and a variable power lens from the front side in the optical axis (L) direction as shown in FIGS. 1 and 23 (a), (b) and (c). (26), field frame (27), eyepiece (28), presser plate (29), and
It is composed of a frame plate (30) and the like. The finder optical system (FS) is housed inside the upper half portion (5B) of the tubular second mounting frame of the integrally molded fixed base plate (5).

As shown in FIG. 1, the upper half (5B) of the fixed base plate (5)
In addition, a near-infrared light emitting element (31) that constitutes a light emitting section for performing automatic focus adjustment by an active method, and a condenser lens (32) and a light receiving element (33) that are light receiving sections are provided. ing. A frame member (34) having a light emitting window (34a), a light receiving window (34b), and a finder window (34c) in a state of covering the light emitting section, the light receiving section, and the front of the finder optical system (FS). Is fixed to the fixed base plate (5).

As shown in FIGS. 1 and 24, (a), (b), and (c), the objective lens holder (35) holding the objective lens (25) in the finder optical system (FS) is It has a tubular portion (35A) along the axis (L) direction. The cylindrical portion (35A) is fitted onto the guide shaft (36) fixedly mounted on the fixed base plate (5) so that the objective lens (25) can move in the optical axis (L) direction. It is configured.

Further, the variable power lens holder (37) for holding the variable power lens (26) is rotatably attached around the axis (X ₇ ) so that the variable power lens (26) can be attached to the finder optical path. It is configured to be able to leave and leave. A spring (not shown) for urging the variable power lens (26) through the variable power lens holder (37) in the direction of inserting it into the finder optical path is provided.

FIG. 23 (a) and FIG. 24 (a) show standard photographing conditions. In this state, the objective lens (2
5) is located at the front end of the moving range. The variable power lens (26) is inserted in the finder optical path by the biasing force of the spring.

23 (b) and FIG. 24 (b) show a finder magnification switching operation which is performed in conjunction with the focal length switching operation in the photographing optical system (PS) described above. As will be described later, the objective lens (25) is configured to be moved rearward (leftward in the drawing) in the optical axis (L) direction in conjunction with the switching of the focal length.

As the objective lens (25) moves, the lower end edge of the objective lens holder (35) comes into contact with and presses the front end face of the variable power lens holder (37). As a result, the variable power lens holder (37) is rotated counterclockwise in the figure against the biasing force of the spring.

Then, as shown in FIGS. 23 (c) and 24 (c), when the objective lens (25) reaches the end of its moving range, the zoom lens (26) is completely removed from the viewfinder optical path. It is configured to evacuate to. This state is the telephoto shooting state, and the finder optical system (FS) is moved by moving the objective lens (25) and retracting the zoom lens (26).
The magnification of is different from the standard shooting condition.

As shown in FIGS. 23 (a) to 23 (c), the eyepiece lens (28) has its stepped portion abutting the stepped portion of the fixed base plate (5) from the front, and at the front end thereof a field frame ( It is positioned by elastically abutting 27).

Further, the frame plate (30) is formed with a semi-transparent plating frame for showing the frame indicating the shooting range within the viewfinder field. The frame plate (30) is positioned by elastically contacting the holding plate (29) from the front side, and the folded portion (29a) of the holding plate (29) contacts from above to prevent the frame plate (30) from coming off. Has been done.

As shown in FIGS. 24 (a) to 24 (c), the cylindrical portion (35A) of the objective lens holder (35) has two portions on the upper and side portions.
Two pins (hereinafter referred to as upper pin and side pin, respectively)
(35a) and (35b) are planted.

Among them, a spring (3) is provided between the upper pin (35a) and the pin (5b) planted on the upper surface of the fixed base plate (5).
8) has been installed. Pin (5b) of fixed base plate (5)
Is located substantially in the center of the moving range of the upper pin (35a) of the objective lens holder (35) in a side view.

The spring (38) is the objective lens holder (35).
When the upper pin (35a) of the is located in front of the pin (5b) of the fixed base plate (5), the objective lens holder (35)
Is biased to the front side and, conversely, when positioned rearward, the objective lens holder (35) is biased to the rear side.

Meanwhile, the side pin (35b) of the objective lens holder (35)
Is fitted in the forked portion (39a) at the upper end of the switching operation lever (39). The switching operation lever (39) is rotatably attached around the axis (X ₈ ), and the objective lens holder (35) is configured to move back and forth in accordance with the rotation. There is.

The objective lens holder (35) is moved forward by the urging force of the spring (38) as described above according to the positions of the upper pin (35a) and the pin (5b) of the fixed base plate (5). It is pressed either in the standard shooting state side or in the backward direction (telephoto shooting state side), and the front end or the rear end of the tube portion (35A) is attached to the back surface (34d) of the frame member (34) or the fixed base plate. The contact portion (5c) of (5) is positioned so as to be positioned.

The switching operation lever (39) has a bevel gear portion (39b) on the side opposite to the forked portion (39a) with the pivot axis (X ₈ ) interposed therebetween. This bevel gear part (39b) includes
As shown in FIGS. 5 (a) and 5 (b), the bevel gear (40) having the gear portion (40a) formed of two teeth only in a part of the circumferential direction faces each other.

This bevel gear (40) is shown in Fig. 1, Fig. 25 (a),
(B) and, as shown in FIG. 26, the spring (41)
Is connected to the gear (42) by. Furthermore, a gear (44) that rotates integrally with a gear (43) that meshes with this gear (42)
However, it meshes with one gear (15a) in the gear train (15) for transmitting drive from the motor (M) in the photographing optical system (PS) to the payout cam (14) already described.

That is, the bevel gear (40) rotates in conjunction with the forward and reverse rotations of the motor (M). The gear portion (40a) of the bevel gear (40) is configured to engage with the bevel gear portion (39b) of the switching operation lever (39) only during the focal length switching operation of the photographing optical system (PS). ing. The meshing between the gear part (40a) and the bevel gear part (39b) causes the switching operation lever (39) to rotate around the shaft center (X ₈ ), and as described above, the magnification of the finder optical system (FS) increases. It is configured to be switched.

28 (a) to (c) show the switching operation lever (39)
And a bevel gear (40) in a planar positional relationship,
In the sectional view seen from the front shown in FIG.
-Expanded along the X-ray.

<< 1 >> Standard shooting state FIG. 28 (a) shows the standard shooting state. The initial state is when the gear portion (40a) of the bevel gear (40) is at the position [a] in the figure. At this time, the shooting optical system (PS)
Is focused at infinity. By driving the motor (M) from this initial state, the bevel gear (40) is rotated clockwise and reaches the position [b] in the figure.

During this time, the focus adjustment operation in the standard photographing state is performed. That is, at the position [b] in the figure, the photographing optical system (PS) is in focus at the closest position.

Also, during this time, the gear part (40a) of the bevel gear (40)
Does not mesh with the bevel gear portion (39b) of the switching operation lever (3). Therefore, the viewfinder optical system (FS)
The magnification has not been switched at, and the viewfinder optical system (FS) has a magnification suitable for standard shooting conditions. At this time, the switching operation lever (39) is in the forward tilted posture as shown in FIG.

<< 2 >> Switching the focal length When switching the focal length from the standard shooting state to the telephoto shooting state, the bevel gear (40) is further rotated clockwise beyond the position [b] in Fig. 28 (a). Gear part (40
a) reaches the position [c] in the figure, and the switching lever (3)
The state immediately before engaging the bevel gear part (39b) of.
During this time, as in the previous case, the magnification change in the viewfinder optical system (FS) is not performed and the viewfinder optical system (FS) remains at the magnification suitable for the standard shooting state in the associative state.

The gear portion (40a) of the bevel gear (40) meshes with the bevel gear (39b) of the switching operation lever (39) during the transition from the position [c] to the position [d] in the figure, and the lever (3).
Rotate 9) counterclockwise in Fig. 27 (b).
As shown in FIG. 28 (b), the gear part (40a) of the bevel gear (40) reaches the position [d] in the figure and the bevel gear part (39).
When the bite with b) is disengaged, the switching control lever (39) moves to the 2nd
As shown by the solid line in Fig. 7 (b), it is in a backward tilted posture.

At this time, the upper pin (35) of the objective lens holder (35) held by the bifurcated part (39a) of the switching operation lever (39).
a) is located rearward of the pin (5b) of the fixed base plate (5), and then the spring (3
The objective lens holder (35) is pushed rearward by the urging force of 8), and accordingly, the switching operation lever (39) moves to the 27th position.
As shown in the figure (c), the posture becomes further backward.

With the rearward movement of the objective lens holder (35), the objective lens (25) moves to the rear end of its moving range, the variable power lens (26) retracts from the finder optical path, and the finder optical system (FS ) Is a magnification suitable for telephoto shooting. Further, the bevel gear portion (39b) of the switching operation lever (39) has moved to the position shown in Fig. 28 (c).

The gear part (40a) of the bevel gear (40) is disengaged from the bevel gear part (39b) of the switching operation lever (39), and then the bevel gear (40) is further rotated, so that the gears (b) and (c) of FIG. ) Is reached, and the bevel gear (40) stops rotating at this position. During this time, the gear part (40a) of the bevel gear (40) is the switching operation lever (39).
The bevel gear part (39b) of this will not engage again. Therefore, the magnification is not switched in the viewfinder optical system (FS) and the viewfinder optical system (FS) remains at a magnification suitable for the telephoto shooting state in the associative state.

Further, in the photographing optical system (PS), the gear part (40a) of the bevel gear (40) is moved from the position [b] shown in FIG. 28 (a) to the position [e] shown in FIG. 28 (c). It is configured such that the focal length is switched while reaching (1). And the gear part (40a) of the bevel gear (40) is the second
When it is at the position [e] in Fig. 8 (c), it is the initial state of the telephoto shooting state. At this time, the shooting optical system (PS)
Is in focus at infinity.

When switching the focal length from the telephoto shooting state to the standard shooting state, the bevel gear (40) is rotated counterclockwise from the position [e] in Fig. 28 (c), and the gear portion (40a) is changed to []. It reaches the position of d '] and engages with the bevel gear part (39b) of the switching operation lever (39).

Then, while the gear portion (40a) of the bevel gear (40) shifts from the position [d '] in FIG. 28 (c) to the position [c'] in FIG. 28 (b), the switching operation lever (39 ) Is rotated clockwise in FIG. 27 (b). Bevel gear (4
When (0) is further rotated and its gear part (40a) is disengaged from the bevel gear part (39a) of the switching operation lever (39), the switching operation lever (39) is shown by the chain double-dashed line in FIG. 27 (b). As you can see, it leans forward. After that, switching operation lever (39)
Is further rotated in conjunction with the movement of the objective lens holder (35) forward by the biasing force of the spring (38).
27 Return to the forward leaning posture in the initial state shown in Fig. 27 (a).

Along with the forward movement of the objective lens holder (35), the objective lens (25) moves to the front end of its moving range, and the variable power lens (26) is inserted into the finder optical path, so that the finder optical system (FS ) Returns to a magnification suitable for standard shooting conditions. Further, the bevel gear (40) is further rotated, and when the gear portion (40a) reaches the position [a] shown in FIG. 28 (a), the rotation is stopped.

<3> Telephoto shooting state The gear (40a) of the bevel gear (40) is located at the position [e] in Fig. 28 (c), and the bevel gear (40) is driven by the motor (M) from the initial telephoto shooting state. ) Is rotated clockwise to reach the position [f] in the figure. During this time, the focus adjustment operation in the telephoto shooting state is performed. That is, at the position [f] in the figure, the photographing optical system (PS) is in focus at the closest position.

Also, during this time, the gear part (40a) of the bevel gear (40)
Does not engage with the bevel gear part (39a) of the switching operation lever (39). Therefore, the viewfinder optical system (FS)
The magnification is not switched at, and the magnification remains at the level suitable for the telephoto shooting state.

That is, as described above, the objective lens holder (35) that can be moved back and forth, the variable magnification lens holder (37) that moves in and out of the finder optical path by swinging, the switching operation lever (39), and the spring (38). ) And the like constitute a finder magnification switching means for switching the magnification of the finder optical system (FS).

Then, as described above, the gear portion (40a) of the bevel gear (40) is provided in the bevel gear portion (39b) of the switching operation lever (39) only when the focal length is switched in the photographing optical system (PS). The lever (39) is rotated around the shaft center (X ₈ ) by engaging with the lens to switch the magnification in the finder optical system (FS).

That is, the bevel gear (40) in which the gear portion (40a) is formed only in a part of the circumferential direction, the spring (41), and the three gears (42) to (44) are the movable members of the operating means ( 15a) and the switching operation lever (39) which is a movable member of the viewfinder magnification switching means are interlocked with each other only when the focal length switching operation in the photographing optical system (PS) is interlocked.

Then, during the focus adjustment operation of the photographing optical system (PS) in the standard photographing state and the telephoto photographing state, the finder magnification switching means in the finder optical system (FS) and the motor (M) are disconnected. Focus adjustment and focal length switching of the shooting optical system (PS) with one motor (M),
In addition, the load of the finder optical system (FS) can be reduced by efficiently using the drive of the motor (M) while the magnification of the finder optical system (FS) is switched.

On the other hand, Fig. 25 (a), (b), and Fig. 29 (a),
As shown in (b), a protruding portion (40b) is formed on the outer peripheral surface of the bevel gear (40) except the gear portion (40a). Further, a projection (39c) is formed on the lower end of the switching operation lever (39).

The overhanging part (40b) of the bevel gear (40) is shown in Fig. 25 (a).
And as shown in Fig. 29 (a), this bevel gear (40)
When the gear part (40a) of the switching operation lever (39) is engaged with the bevel gear part (39b) of the switching operation lever (39), the switching operation lever (39) is not in contact with the protrusion (39c). It does not prevent rotation around the shaft center (X ₆ ) of 39).

In addition, as shown in FIG. 25 (b) and FIG. 29 (b),
The gear part (40a) of the bevel gear (40) is connected to the switching operation lever (3
9) The bevel gear (39b) is not engaged and the viewfinder optical system (FS) has a magnification suitable for either standard shooting or telephoto shooting. (40b) is in a position facing the protrusion (39c) of the switching operation lever (39).

The overhanging portion (40b) of the bevel gear (40) and the protrusion (39c) of the switching operation lever (39) are slightly apart from each other. In this state, if some external force acts on the viewfinder optical system (FS) to rotate the switching operation lever (39) around the axis (X ₈ ), the switching operation lever (39) will rotate slightly and The protrusion (39c) is the protruding part (40b) of the bevel gear (40).
To prevent the subsequent rotation of the switching operation lever (39) around the axis (X ₈ ). This prevents movement of the objective lens holder (35) to a position where the upper pin (35a) of the objective lens holder (35a) exceeds the pin (5b) of the fixed base plate (5), and the switching operation lever (39) moves to the spring (38). Return to the correct position by the urging force of.

That is, even when vibration or the like is applied, the magnification of the finder optical system (FS) is prevented from being inadvertently switched.

In the previous embodiment, in the operation mechanism for sliding the main lens (4a) which is the front lens of the photographing optical system (PS) to the retracted position side against the biasing force of the spring (6), the motor (M) The interlocking feeding cam (14) is the operating side member, and the feeding lever (18) interlocking with the shutter block (4) holding the main lens (4a) is the operated side member, and the feeding cam (14) and the feeding lever are Although the structure is configured to allow the operation-side member to operate toward the retracted position by forming an accommodation with (18), the specific structure of the operation mechanism can be appropriately changed. Next, several examples will be described.

The one shown in FIG. 31 has a base plate (45) for holding a front lens (not shown in the figure) of the photographing optical system (PS) along a pair of guide rods (46a) and (46b). The base plate (45) is configured to be slidable back and forth, and the base plate (45) is biased forward by the spring (6) and abuts from the front of the base plate (45) to resist the biasing force of the spring (6). Base plate (45)
The restriction member (47) for restricting the movement of the screw is screwed onto the male screw member (48) that rotates in conjunction with the motor (M).

In the case of this configuration, the restriction member (47) is a base for allowing the operation of the base plate (45), which is the operated member, to the retracted position side with respect to the restriction member (47), which is the operation side member of the operation mechanism. The plate (45) is formed so as to abut against the plate (45) from the front side in a one-sided contact state to allow the base plate (45) to move to the rear side.

FIG. 32 shows a modification of the configuration shown in FIG. 31. Instead of screwing the restricting member (47) and the motor (M), a rack formed on the restricting member (47) ( 47
It is designed to be linked by a) and a pinion (49) linked to the motor (M). Other configurations are 31st
Since the configuration is the same as that shown in the figure, the same numbers are used only and the detailed description is omitted.

It should be noted that the number of switching steps of the focal length in the photographing optical system (PS) may be three or more.

〔The invention's effect〕

As described above, according to the present invention, when the front lens is in the projecting position, a shock is applied to the member for holding the front lens or the camera is placed with the front lens side facing down to move the front lens. Even if the weight of the camera body is applied to the holding member, the optical system is allowed to retreat against the urging of the urging means by being released from the pressing by the pressing portion, so that the front lens is held. Since the force applied to the member is absorbed, there is an effect that an excessive force is not applied and the member is not damaged.

Further, even if the operation is blocked from the front while driving in the direction of projecting the front lens, it is allowed to separate from the pressing portion and stop the feeding of the optical system. This has the effect of avoiding breakage due to damage.

Further, when the external force disappears, the urging force of the urging means causes the optical system to return to the original position determined by the pressing portion, so that it automatically returns to the original state, and the effect that shooting can be continued is achieved. Of.

[Brief description of drawings]

The drawings show an embodiment of a focal length switchable camera according to the present invention. FIG. 1 is an exploded perspective view of a photographing optical system and a viewfinder optical system, FIG. 2 is an overall plan view, and FIGS. B)
Fig. 3 is a rear view of the shutter block. Fig. 3 (a) shows a standard shooting state, Fig. 3 (b) shows a telephoto shooting state, and Fig. 4 is an enlarged rear view of the main part of the shutter block in the standard shooting state. 5 is an exploded perspective view of the shutter block, the movable lens barrel, and a part of the retracting means for the sub lens, FIG. 6 is an exploded perspective view of a part of the retracting means for the sub lens, and FIG. Partial enlarged side view of the means for moving the lens in and out, No.
FIG. 9 is a perspective view of the cam surface of the fixed base plate, and FIGS. 9 (a) to 9 (c) are schematic plan views showing the relationship between the shutter block, the movable lens barrel, and the retracting means for the auxiliary lens. (A) is the standard shooting state, FIG. 9 (b) is the focal length switching state, FIG. 9 (c) is the telephoto shooting state, and FIG. 10 is a perspective view of the shooting optical system in the standard shooting state. The figure is a perspective view of the feeding cam and the feeding lever, FIG. 12 is a sectional view of the feeding cam and the feeding lever, FIG. 13 is a plan view of the feeding cam, and FIG.
FIG. 15 is a development view of the focus adjusting cam surface on the short focal length side of the feeding cam, FIG. 15 is a plan view of adjusting means for the support lever of the feeding lever, and FIG. 16 is a plan view of a position detecting brush of the feeding cam. Figure 17 is a plan view of the gear base plate position detection pattern.
FIG. 18 is a bottom view of the gear base plate, FIG. 19 is a circuit diagram of the periphery of the control device, and FIGS. 20 (a) to 20 (e) are plan views of the drive mechanism for the photographing optical system. ) Is the standard shooting state and the shooting optical system is in focus at infinity.
Figure (b) shows the standard shooting state with the photographic optical system focused on the closest position. Figure 20 (c) shows the 20th shot when the focal length is switched.
Figure (d) is the initial state when the shooting optical system is focused on the infinity position in the telephoto shooting state, and Figure 20 (e) is the state that the shooting optical system is focused on the closest position in the telephoto shooting state. Respectively,
FIG. 21 is a flow chart of the focus adjustment operation, FIG. 22 is a flow chart of the focal length switching operation, FIGS. 23 (a) to 23 (c) are longitudinal sectional views of the finder optical system, and FIG. 23 (a) is a standard photographing. Fig. 23 (b) shows the focal length switching, Fig. 23 (c) shows the telephoto shooting state, and Figs. 24 (a) to 24 (c) are side views of the viewfinder magnification switching means. Figure (a) shows the standard shooting state, Figure 24 (b) shows the focal length switching, Figure 24 (c) shows the telephoto shooting state, and Figure 25 (a) and (b) shows the switching operation lever. 25A and 25B are cross-sectional views showing the engagement with the bevel gear, FIG. 25A shows the focal length switching, FIG. 25B shows the focus adjustment, and FIG. 26 is a schematic cross-sectional view of the interlocking means. Figures (a) to (c) are side views of the switching operation lever. Figure 27 (a) shows the standard shooting state, Figure 27 (b) shows the focal length switching, and 27 ( ) Indicates the telephoto shooting state, and FIGS. 28 (a) to 28 (c) are XX line development views in FIG. 25 (a) showing the relationship between the bevel gear portion of the switching operation lever and the gear portion of the bevel gear. , 28th
Figure (a) shows the standard shooting state, Figure 28 (b) shows the focal length switching, Figure 28 (c) shows the telephoto shooting state, respectively, and Figures 29 (a) and (b) show the switching operation lever. FIG. 29 (a) is a plan view showing the relationship between the protrusion and the protruding portion of the bevel gear, FIG. 29 (a) shows the focal length switching, and FIG. 29 (b) shows the focus adjustment.
FIG. 30 is a plan view of a part of a camera showing another embodiment of the switching operation tool, and FIGS. 31 and 32 are schematic views showing another embodiment of the focal length switching mechanism, respectively. (3) …… Camera body, (4a) …… Front lens, (6) ……
Spring, (14), (47) ... Operation side member, (18),
(45) …… Operated member, (PS) …… Shooting optical system.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical indication G03B 13/36

Claims (1)

[Claims] 1. A focus adjustment of an optical system is performed by moving the optical system between a position where a front lens of a photographing optical system projects forward from a camera body and a position retracted rearward from the position. The camera has a biasing unit that biases the optical system in a direction of projecting forward, and a pressing unit that presses the optical system rearward against the bias of the biasing unit. By changing the pressing position, the position of the optical system with respect to the optical axis direction is arbitrarily adjusted, and thereby the moving unit for adjusting the focus of the optical system, and the optical system in the entire region of the pressing portion of the moving unit. Is released from the pressing by the pressing portion, and a retreat allowance region is formed which is movable rearward from the position adjusted by the pressing portion against the bias of the biasing means. Focus adjustment device.