JPH02114247A - Interchangeable lens camera - Google Patents

Abstract

PURPOSE:To eliminate the need of a motor, etc., in an interchangeable lens and to make the constitution of an entire lens barrel compact by providing a compact area housing a focusing lens on the extension of an autofocusing mechanism which drives the focusing lens. CONSTITUTION:The compact area is provided, where the focusing lens L1 is fed in the side of a film surface more than the infinity end position of an ordinary photographing area. Since the focusing lens L1 is made to be fed in the compact area with the driving force of a focusing driving motor 104, the length of the lens can be shortened in a method for driving the lens same as focusing action. Since barriers 7 and 7' are provided for the focusing lens L1 so as to block the lens by interlocking with the movement of the focusing lens L1 to the compact area, they are automatically closed at the time of housing the lens. Thus, the length of the lens can be shortened at the time of completing photographing and blocking by the barriers 7 and 7' is performed by interlocking with the above-mentioned action, thereby improving compactness and operability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an interchangeable lens camera constructed by combining an interchangeable lens having a barrier and a camera body.

[Conventional technology]

2. Description of the Related Art Zoom lenses have conventionally been known in which the lens barrel is retracted from the normal photographing area toward the film plane to shorten the lens length.

For example, in Japanese Patent Publication No. 51-40459, a limiting member for limiting the infinity position is provided in the zoom lens barrel, and when the lens is not in use, the zoom means is released and the focusing operation member and zooming operation member are integrated. A zoom lens is shown in which the limiting action of the limiting member is released and the focus lens group is retracted beyond the infinity position toward the film surface. In this reference, the lens length of a zoom lens is shortened by complicated manual operation, and the mechanism is difficult to shorten the lens length by motor drive.

Further, a retractable camera with a barrier is known in which the zoom lens retracts into the body when not photographing, and a barrier is opened and closed in conjunction with this. For example, in Japanese Utility Model Application No. 61-188112, a collapsing cam groove is continuously provided in a zooming cam groove of a zoom lens with a barrier,
A zoom built-in lens is shown in which the zoom lens can be stored in the camera body, and a barrier shields the front surface of the lens in conjunction with the lens storage.

Furthermore, Japanese Patent Application Laid-Open No. 62-69254 discloses a barrier drive means, a lens drive means, and a control cam means integrally configured to control the drive of these drive means, respectively, and the control cam A collapsible camera with a barrier is shown in which the operation of the lens and the operation of the barrier driving means are synchronized by the cam operation of the means, and the collapsing of the lens and the opening/closing of the barrier are controlled.

Further, in Japanese Utility Model Application No. 62-193228, a lens drive ring driven by a motor is provided on the outer periphery of the lens holding frame, and a barrier opening/closing section is provided as an extension of the collapsible section of the lens barrel, and a barrier of the drive ring is provided. A barrier mechanism of a collapsible lens shutter camera is shown in which the barrier is opened and closed in conjunction with the rotational movement of the opening and closing sections.

Furthermore, Japanese Patent Application Laid-open No. 63-95426 discloses that a camera in which the focal length can be switched in two steps, telephoto and wide, is provided with a member that is linked to a focal length switching motor, and the driving force of the motor is transmitted through this member. A version with a barrier that opens and closes is shown.

[Problem to be solved by the invention]

By the way, the prior art of the retractable camera with a barrier disclosed in the above publication relates to a so-called compact camera in which the lens and the body are integrated.In an interchangeable lens camera in which the body and lens are combined, the lens There is no known technology in which the barrier can be shortened to a compact size and the barrier can be opened and closed in conjunction with this.

In the conventional technology related to the above-mentioned compact cameras, when shortening the zoom lens, the zoom ring is rotated to shorten the lens length, but with interchangeable lens cameras, the zoom ring is rotated to shorten the lens length. In this case, since the interchangeable lens 111 includes a single-focus lens without a zoom ring, it becomes difficult to systemize the camera. In addition, in the case of an interchangeable lens camera that uses an autofocus device 111+1, the focusing lens and zooming lens are driven by a motor.
The structures of the camera body and lens barrel become more complicated, and the disadvantages in terms of cost also become greater.

In addition, when opening and closing the barrier in conjunction with the shortening of the lens in an interchangeable lens camera, it is possible to further increase the As the structure of the interchangeable lens barrel becomes more complex, it also becomes difficult to control these actuators.

The present invention has been made in view of the above problems, and is an interchangeable lens that shortens the lens length at the end of shooting and closes the barrier in conjunction with this, and has the compactness and operability of a compact camera. The purpose is to provide a type camera.

[Means to solve the problem]

To achieve the above object, the present invention provides an interchangeable lens camera that includes a focusing lens driving motor within a body, and in which the driving force of the driving motor is transmitted to the focusing lens via a focusing coupler. a compact area which is moved further toward the film surface from the infinity end position of the normal shooting area, a barrier that shields the focusing lens, and a driving force of the focusing lens driving motor to move the compact area from the normal shooting area of the focusing lens. The device includes a barrier opening/closing mechanism that closes the barrier in conjunction with retraction into the area.

Further, in the interchangeable camera, the focusing lens is extended from the compact closed area to the normal photographing area when the main switch is turned on, and the focusing lens is retracted into the compact area when the main switch is turned off.

[Effect]

According to the interchangeable lens camera having the above configuration, a compact area is provided in which the focusing lens is extended further toward the film surface from the infinity end position of the normal photographing area, and the focusing lens is moved into the compact area by the driving force of the focusing drive motor. Since the lens is retracted into the lens, the lens length can be shortened using the same lens driving method as in the focusing operation. Further, since the focusing lens is provided with a barrier and the barrier is closed in conjunction with the movement of the focusing lens to the compact area, the barrier is automatically closed when the lens is stored.

Further, since the main switch controls the focusing lens to move into the compact area and the edge of the focusing lens, when the main switch is turned on, the focusing lens is moved out from the compact area to the normal shooting area and takes pictures. When the focusing lens is enabled and turned off, the focusing lens is retracted into the compact area.

〔Example〕

An embodiment of an interchangeable lens camera with a single focus lens according to the present invention is shown in FIGS. 1(a), 1(b), and 6(c). Figures (a), (b), and (e) show the positions where the focusing lens is retracted further toward the body from the near end, infinity end, and infinity end (hereinafter referred to as compact (referred to as a region). Further, the right side of each figure is a side sectional view of the configuration of the interchangeable lens type camera, and the left side shows the configuration of the barrier when looking from the lens side to the camera body side.

In FIG. 1, to explain the configuration of the interchangeable lens type camera, switch SWM is the main switch of the camera 7u source;
A CPU 102 is a microcomputer that controls the photographing operation of the camera, and a sensor 103 is a microcomputer that controls the photographing operation of the camera.
Focus sensor and mirror 104 that detect (D)
is a sub-mirror that reflects light to the focus sensor 103, and a drive circuit 105 includes a focusing motor (FM), and is a focusing motor drive circuit that drives the motor. The coupler 4 is a focusing coupler that transmits the rotational force of the focusing motor to the interchangeable lens side, and the rotational force of the focusing motor is transmitted through the gears 22 to
24 to the focusing lens L1.

Further, the lens ROM101 is a memory that stores lens information specific to the interchangeable lens, and is a memory that stores lens information specific to the interchangeable lens.
102 is a switch SWI, information from SW2 (described later),
It transmits the conversion coefficient of the lens driving amount and the rotation direction information ROT of the focusing motor when moving the focusing lens L1 from the near side to the infinity side. This information is R if the rotation direction is right.
If it is OT-1, left, it is represented as ROT-0.

In the above configuration, main switch SWM is turned on and C
When the PU 102 performs autofocus (AF) control, the CPU 102 calculates the driving amount of the focusing motor using the defocus mD of the subject image from the focus sensor 103 and the conversion coefficient K from the lens ROM 101, and uses the control signal and the AF control. A signal indicating the focus direction is manually input to the focusing motor drive circuit 105.

The focusing motor drive circuit 105 drives the focusing motor by a predetermined amount and in a predetermined direction.
The focusing lens L1 moves to the focusing position and is automatically focused.

Next, the configuration of the interchangeable lens will be explained. The fixed tube 1 has a ring M ring 2 on the outer periphery and a helicoid screw la.

It is screwed together with 2a. Further, a gear 25 is formed on the inner peripheral surface of the distance ring 2, and is screwed into the gear 24. The rotation of the focusing motor is transmitted to the distance ring 2 via the focusing coupler 4 and gears 22 to 24, and the distance ring 2 is moved in the optical axis direction while rotating.

A moving frame 3 in which a focusing lens L1 is rotated is bayonet-coupled to the tip of the distance ring 2. The moving frame 3 does not rotate in the direction of rotation of the distance ring 2, but moves integrally with the distance ring 2 in the optical axis direction, and the movement of the moving frame 3 in the optical axis direction moves the focusing lens L1. You can also move the lens to adjust the focus. Note that the moving frame 3 can continuously move between the normal imaging area (from the near end to the infinite distance end) and the compact area.

A barrier rotating plate 5 and a front lens barrier 7,7' are provided at the front of the moving frame 3, and an aperture regulating plate 9 for regulating the aperture area of the lens is further provided at the front thereof. Further, an opening 9a is formed in the inner diameter part of the aperture regulating plate 9, and when the two front lens barriers 7.7' are fully opened, the barrier 7.7' is retracted from the opening 9a to the outside. It is hidden from view.

In the front lens barrier 7.7', barrier rotation interlocking pins 7c and 7c' are connected to U'7' of the barrier rotation plate 5, respectively.
? 1η5 b + 5 b' and is supported by barrier rotation shafts 7b and 7b'. Barrier rotating plate 5
are normally biased counterclockwise by barrier springs 8.8', and the stopper contact portions 5c, 5 of the barrier rotating plate 5
c' comes into contact with the stopper bin 10.10', and the front lens barrier 7.7' is stopped in the fully open state. When the barrier rotation plate 5 rotates clockwise, the barrier rotation interlocking pins 7c, 7c' also rotate together, and the front lens barrier 7.7' moves inward around the barrier rotation axes 7b, 7b'. It is rotated and engages at the center of the opening 9a to shield the focusing lens L1.

The switches SWI and SW2 detect the position of the focusing lens L1 and are provided on the lens barrel fixing section, and the on/off states of the switches SWI and SW2 are sent from the lens ROMI 01 to the CPU 102. Further, the switch SW1. SW2 on/off
When the off-switching contact piece 11 is in contact and the barrier rotary plate 5 rotates clockwise as the distance ring 2 rotates,
The switching contact piece 11 is pushed by the projection 5a, so that the contact point of the switching contact piece 1 is switched from switch SWI to switch SW2.

Here, with respect to the rotation angle of the distance ring 2, switch SW1.
FIGS. 2(a) and 2(b) show position information of the focusing lens L1 detected by SW2.

This will be explained using (c) and FIGS. 3(a), (b) to (e).

2(a), (+3), and (e) show the positional relationship of the stopper plate 6 and the protrusion 5a accompanying the moving frame 3 with respect to the rotation angle of the distance ring 2. In addition, Fig. 3 (a), (b) - (e) are similar to Fig. 2 (a), (b).
), The bayonet end of the distance ring 2 in (c) is shown enlarged and straightened for convenience of explanation. and,
(a) of each figure.

(b) and (c) are the near end of Fig. 1 (a), (11)
The infinity end corresponds to the position of the focusing lens L1 in the (C) compact region.

At the short distance end in FIG. 3(a), the bayonet end 2a of the distance ring 2 comes into contact with the abutting portion 6a of the stopper plate 6, and the rotation of the distance ring 2 is stopped.

When the distance ring 2 is rotated clockwise and the focusing lens L1 is at the infinity end position (FIG. 3(b)), the bayonet end 2b of the distance ring 2 is removed and the protrusion of the rear rotary plate 5 is removed. 5a. Then, when the distance ring 2 is further rotated, the protrusion 5a is pushed by the yonet end 2b,
The barrier rotating plate 5 starts rotating. At this time, as shown in Figure 1 (b
), the contact piece 11 that was in contact with the switch SW1
is pushed by the projection 5a and separated from the switch SWI, and both the switches SWI and SW2 are turned off. When this switch SWI is turned off, it is detected that the focusing lens L1 has reached the infinity end.

Next, when the distance ring 2 is further rotated clockwise, the protrusion 5a comes into contact with the contact portion 6a of the stopper plate 6, and the rotation of the distance ring 2 is stopped (FIG. 3(C)). The front lens barrier 7.7' is completely closed at the opening 9a as shown in FIG. 1(C), and the focusing lens L
1 completely shielded.

Also, the contact piece 11 that was in contact with the protrusion 5a is
When W2 is contacted, the switch SW2 is turned on.

In FIG. 3, the rotation angle D2 is the rotation angle from the near end of the bayonet end 2a to the infinity end of the bayonet end 2b, and the rotation angle D3 is the angle of rotation from the infinity end of the bayonet end 2b to the infinity end. This is the rotation angle up to the far end overshoot. Then, the rotation angle DI (-D2+D3) is the distance ring 2
With this amount of rotation, the focusing lens L1 moves from the compact region to the short distance end.

Switch S for the rotation angle (θ) of the above distance M m 2
Table 1 shows the relationship between the on/off information of WI and SW2 and the opening/closing of the barrier.

Table 1 shows lens R as position information of focusing lens L1.
It is sent to the CPU 102 from OM10I.

Based on this information, the main switch SWM is turned on (
When photographing is started (or ended) by (or off), the focusing lens Ll is advanced from the compact area (or is retracted into the compact area), and in conjunction with this, the opening and closing of the front lens barrier 7.7' is controlled.

Table 2 shows the relationship between the main switch swM, the switch SW2, and the driving of the focusing motor.

The above switch SW1. FIGS. 4(a), 4(b), and 4(c) show an embodiment of an interchangeable lens type camera using a zoom lens for the ON/OFF information method of SW2.

In the same figure, Figure 1 (a), (b), (e)
The same symbols are used to indicate the same month. Focusing is performed by driving the lens L2, and zooming is performed by driving the lenses L2 and L3. 28 is a zoom operation ring;
9 is a zoom cam ring, 31 is a first moving frame, and 32 is a second moving frame. For zooming, use the zoom control ring 2
This is done by rotating 8. That is, when the zoom operation ring 28 is rotated, the zoom cam ring 29 rotates integrally with the zoom operation ring 28. First moving frame 31
is a pin that fits into a cam groove formed in the zoom cam ring 29, and when the zoom cam ring 29 rotates, it receives the rotational force. However, since the first moving frame 31 is prohibited from rotating by a linear mechanism (not shown), it does not rotate and moves straight by the lead of the cam.

Further, helicoid threads are formed on the outer surface of the first moving frame 31 and the inner surface of the distance ring 2, and the first moving frame 31 is engaged with the distance ring 2 by the helicoid screws, so that the suppression 1111 fjff 2 is When the vehicle moves straight, the first moving frame 31 moves straight. On the other hand, the second moving frame 32 has a pin that passes through a straight groove of the fixed barrel and fits into another cam groove formed in the zoom cam ring 29, and moves straight as the zoom cam ring 29 rotates.

Focusing is performed by rotating the distance ring 2 in exactly the same way as in the above embodiment. As shown in the figure, even when the interchangeable lens is a zoom lens, the distance Ill ring 2 is rotated by the rotational force of the focusing motor, and the focusing lens group L2 is retracted into the compact area, as in the case of a single focal length lens. The length is shortened. Also,
Focusing lens 7! When $L2 is retracted into the compact area, the front lens barrier 7°7' is closed in conjunction with this, and the focusing lens group L
2 is rolled out from the compact area, the front lens barrier 7.7' is opened in conjunction with this.

Next, a sequence for controlling the opening and closing of the barrier in accordance with the start or end of imaging using the main switch SWM will be described using FIG. In Figure 5,
#10 to #50 are normal shooting conditions (Fig. 1 (a) = (
This is a flowchart when the main switch SWM is turned from on to off in case b) or FIG. 4 1+), (b) case).

That is, when the main switch SWM is turned off in the normal shooting state, the power is turned on to bring the focusing lens L1 or L2 into the compact area (#10,
#15). Since the switch SW2 is in the OFF state, the rotation direction information of the focusing motor (FM) ROT
, rotate the focusing motor (FM) from the near end to the infinity end, and then rotate the focusing motor (FM) in the direction beyond which the focusing lens L1 or L2 is retracted until switch SW2 is turned on (#20 to #40). . When the switch SW2 is turned on, the focusing lens L1 or L2 is completely fitted into the compact area, and the front lens barrier 7.about.7' is also closed, so that the focusing motor is stopped. Furthermore, when a timer (not shown) that starts operating when the main switch SWM is off and the switch SW2 is turned on measures a predetermined time, the power is turned off and the process ends (#40 to #50).
If the main switch SWM is turned off with the focusing lens L1 or L2 already retracted into the compact area, the switch SW2 is turned on in #20, so the focusing lens L1 or L2 will not be moved, so #50 Jump to , turn off the power that was started in #15, and exit (#50).

Next, in #60 to #90, the focusing lens L1 or L2 is in the compact area, that is, the area where the front lens barrier 7.7' is in the closed state (FIG. 1(e) or FIG. 4(C)), This is the flow of turning on the main switch SWM from the stored state to enter the shooting state.

In other words, when the main switch SWM is turned on (#IQ
), turn on the power to move the focusing lens from the compact area to the normal shooting area (#60)
. Since the switch SW2 is on, check the rotation direction information ROT of the focusing motor, rotate the motor from the position past the infinity end to the infinity end position, and close the front lens barrier 7.7'. Open, switch SW
Focusing lens L1 or L2 until 2 turns off
(#65 to #85). When the switch SW2 is turned off, the focusing lens L1 or L2 is extended to the normal shooting area, so it enters the shooting state (
#85. #90).

Next, #90 to #170 are the flow at the time of photographing. When the focusing lens L1 or L2 is extended to the normal shooting CJ'l area, it is checked whether the A17 start switch SW3 is on (it is turned on when the shutter button is pressed halfway), and if it is off, steps #65 to #90 are turned on. Run the loop and wait until it is turned on. If it is on, it is determined whether the focus detection result is reliable or not depending on the state of the focus detection device (#95). If the contrast of the subject image is low (hereinafter referred to as low contrast) or dark (hereinafter referred to as low light), it is determined that the image is unreliable. If reliable, perform focus detection and focus calculation,
The focusing motor is driven to move the focusing lens L1 or L2, a loop from #100 to #110 is executed, and when the focusing position is reached, the focusing motor is stopped (#115). Then, when the shutter button is pressed and photographing ends, the process returns to #10 (#120). In addition, if you return to #10 at #120 and start the next shooting, press the main switch swM,
Since the power is on, the focusing lens L1 or L2 is in the normal photographing range, and the switch SW2 is off, the process moves from #65 to #90.

If #95 is unreliable, focus lens L1
Or check whether L2 is not at the infinite end (#1
25). The fact that the focusing lens L1 or L2 is at the infinite end is detected by turning off the switch SW1. If the focusing lens L1 or L2 is not at the infinity end (SWI is on), check whether the focusing lens L1 or L2 is in a reliable state while retracting it into the camera body (#1
30,6135). If it becomes reliable, #10
0 and the focusing lens L1 or L2 is retracted to the infinite end without reliability (#14
0 (No), the rotation direction of the focusing motor is reversed and focusing lens L1 or L2 is extended to check whether a reliable state is achieved (#145 and #150). Once the reliability is achieved, the process moves to #100, and if the focusing lens L1 or L2 is extended to the short distance end without being reliable (N at #150).
O, "None" in #155), the number of revolutions of the motor is monitored by an encoder, and the output pulses of the encoder are counted by a counter. The fact that the focusing lens L1 or L2 is at the short distance end is detected when the counter output disappears in #155.

If the focusing lens L1 or L2 is at the infinity end in #125 (SWI is off), the process moves to #145, and as described above, the focusing lens L1 or L2 is extended toward the near end, and a reliable Check for the presence or absence of a condition.

〔Effect of the invention〕

As described above, according to the present invention, the driving force of the focusing drive motor provided in the camera body is transmitted to the focusing lens via the focusing coupler, and the autofocus (
Since a compact area for housing the focusing lens is provided in the extension of the AF mechanism, a motor or the like is not required within the interchangeable lens, making the overall structure of the lens barrel compact. Also,
Since the basic configuration is an AF interchangeable lens, there are fewer additional parts and there are cost benefits.

In addition, since the lens extension range (particularly the overextension of the lens) necessary for temperature guarantee can be used as the extension amount from ω when storing the lens, the design space is advantageous and a complicated mechanical structure is not required.

Next, when you turn off the main switch to finish shooting, the focusing lens is automatically retracted into the compact area and the barrier is closed, and when you turn on the main switch to start shooting, it automatically The barrier is opened and the focusing lens is extended from the compact area to the normal shooting area and ready to take pictures, so the photographer does not have to worry about putting on or taking off the lens cap, and it works just like a lens-shutter camera. Simple 111
You can freely enjoy taking photos at any time with simple operations. Additionally, the focusing lens can be stored compactly after shooting, making it convenient to carry.

[Brief explanation of the drawing]

FIGS. 1(a), 1(b), and 1(c) show an embodiment of an interchangeable lens camera with a single focus lens according to the present invention. Fig. 2 (a), (b), (c) are diagrams showing the positional relationship of the stopper plate and the barrier rotating plate with respect to the rotation angle of the distance ring. FIGS. 3(a), (b), and (c) are enlarged views of the bayonet portions of the distance rings shown in FIGS. 2(a), (b), and (c). Figure 4 (a), (b),
(c) is an embodiment of an interchangeable lens camera with a zoom lens according to the present invention. FIG. 5 shows a flow chart in which the driving of the focusing lens is controlled by turning on and off the main switch. 2... Distance ring, 3, 31.32... Moving frame, 4...
・Focusing coupler, 5...Barrier rotating plate, 6・
...Stopper plate, 7.7'...Front lens barrier, 9...Aperture regulating plate, 11...Switching contact piece, 2
2 to 24...Gear, 101 = L/Ns ROM,
102 mountain CPU. 104...Focusing motor drive circuit, SWI. SW2, SWM... switch, Ll, L2. L3...
・Lens group. Patent applicant Minolta Camera Co., Ltd. Representative
People Patent Attorney Etsu Kotani Kawamukai
Chief Patent Attorney 1) Masamukai Patent Attorney fJI Takao Fuji Diagram Procedure Amendment (Method) 1. Indication of the case 1988 Patent Application No. 268752 2. Name of the invention Interchangeable lens camera 3. III Person making correction 4, date of agent amendment order: March 7, 1999

Claims (1)

[Claims] 1. In an interchangeable lens camera that has a focusing lens driving motor within the body and in which the driving force of the driving motor is transmitted to the focusing lens via a focusing coupler, the focusing lens is normally A compact area that is drawn further toward the film surface from the infinity end position of the imaging area, a barrier that shields the focusing lens, and a driving force of the focusing lens driving motor from the normal imaging area of the focusing lens to the compact area. An interchangeable lens camera comprising: a barrier opening/closing mechanism that closes the barrier in conjunction with retraction of the barrier. 2. The focusing lens according to claim 1, wherein when the main switch is turned on, the focusing lens is extended from the compact area to the normal photographing area, and when the main switch is turned off, the focusing lens is retracted into the compact area. Interchangeable lens camera.