JPS6350686B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an interchangeable lens equipped with an automatic focusing device. A detection device detects the distance of the object to be photographed, and the object distance information is converted into a binary electric signal based on the signal from the detection device. The information corresponding to the set distance is converted into a binary electric signal, and the object distance information and distance ring information are compared, and the distance ring driving means such as a motor controls the movement of the photographing lens in the optical axis direction. For example, an automatic focusing device and system for detecting the in-focus position of
There is specification number 22906 etc. Since the present invention has these automatic focusing devices mounted on an interchangeable lens, it is possible to perform automatic focusing photography, and also to select an appropriate automatic focusing mode according to the attachment and detachment of the battery case. To provide an interchangeable lens equipped with a device.

Next, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 7.

FIG. 1 shows the distance ring 1 described above, a code plate 4 for converting the position of the distance ring on the distance scale into an electrical signal (digital signal), and an electrode part sliding on the code plate 4. A plurality of brushes 5a are shown, and the brushes form a switch group _S2 shown in FIG. 3 by rotating and sliding on electrode portions and non-electrode portions on the code plate.

FIG. 2 shows an overall transparent perspective view of an embodiment of the present invention in which an automatic focus adjustment device is mounted on an interchangeable lens L of a single-lens reflex camera. The lens barrel structure of the interchangeable lens barrel of the interchangeable lens L shown in FIG.
(Japanese Patent Application Publication No. 17927-1983), and Utility Application No. 1983
No. 96744 (July 9, 1982)
No. 96746 (July 9, 1982)
(Japanese Utility Model Application No. 57-23507), etc., so detailed explanation will be omitted.

In FIGS. 1 and 2, the code plate 4 is attached to the fixed barrel of the lens barrel or the exterior frame with screws, etc., and the brush 5a of the code plate is attached to the brush holding plate 5 by caulking 5b etc. Fixed. The brush holding plate 5 is fixed to a crown gear 7 forming part of the gear train of the motor M by screws 7a and washers 7b.The brush 5a slides on the electrodes of the code plate 4 as the motor M rotates. . When the distance ring 1 is grasped and turned manually, the rotation of the distance ring 1 is transmitted to the gears 2 and 3 that mesh with the gear portion 1a provided on the outer periphery of the distance ring 1, which further rotates the crown gear 7 and rotates the brush. 5a
Rotate. The first switch SW ₃ shown in Figure 1
is a switch that opens and closes by rotating the distance ring 1, and the distance value (scale value) set by the distance ring 1
It is configured so that it is closed (ON) within a range of 1 m.

FIG. 3 shows the control circuit of this embodiment. In the circuit, the symbol G indicates that the terminal is connected to ground. IC ₁ indicates a line sensor of known autofocus technology, and IC ₂ and IC ₃ are integrated circuits that constitute a distance measurement circuit, which inputs the signal from line sensor IC ₁ and converts object distance information into an electrical signal (e.g. It also outputs signals for driving the motor M and other signals required for automatic focus control. The technical details regarding the line sensor IC ₁ , distance measuring circuit IC ₂ , and IC ₃ are disclosed in the aforementioned patent application filed in 1973.
- Since it is detailed in the specification of No. 22906, it will be omitted.
The control circuit in Figure 3 includes the rotation control circuit (DCC) of the motor M, the drive signal formation circuit (DSFC), the power supply voltage check circuit (BCC), the sound generation circuit (SMC), the sound generation control circuit (SCC), and the motor drive prohibition circuit. Each of these circuits is mounted on a circuit board 8 shown in FIG. 2, and the circuit board 8 is screwed onto a support frame 9 and fixed onto the lens barrel. be done.

Next, each circuit shown in FIG. 3 will be explained in detail.

1 IC ₂ and IC ₃ are integrated circuits constituting a distance measuring circuit, and since the distance measuring circuit is described in detail in the aforementioned Japanese Patent Application No. 54-22906, a detailed explanation thereof will be omitted. The integrated circuit IC ₂ has output terminals 1 to 7, from which transfer pulses φ _{1 to 7} are respectively transmitted.
_φ4 integration clear pulse φIC,
A shift pulse φSH and a reset pulse φR are output, and these pulses are applied to the line sensor IC ₁ , and the line sensor IC ₁ outputs an image scanning output Vos and a voltage fluctuation information output V _DOS , which are then sent to the integrated circuit IC ₃ . input. the integrated circuit
IC ₃ is the output Vos, V _DOS from line sensor IC ₁
Line sensor IC ₁ along with integrated circuit IC ₂
A digital value as a distance measurement signal corresponding to the subject distance measured by is calculated. integrated circuit
Terminals 8 to 14 of IC ₂ input digital values as set distance signals formed by switches S _2-1 . . . S _2-6 , and compare the digital values with the digital values as the distance measurement signals. The integrated circuit IC ₂
has output terminals A to D that output signals for controlling the motor drive circuit, and depending on the comparison result between the distance measurement signal and the set distance signal, if the distance measurement signal>the set distance signal, the output signal is output. A high level signal (hereinafter referred to as 1 signal) is output from terminals A and C, and a low level signal (hereinafter referred to as O) is output from output terminals B and D.
It is called a signal. ) is output. In addition, if the distance measurement signal < the set distance signal, the O signal is output from the output terminals A and C, and the 1 signal is output from the output terminals B and D, and the distance measurement signal =
In the case of a set distance signal, a 1 signal is output from output terminals A and B, and a 0 signal is output from output terminals C and D. A circuit for this output is disclosed in said application. Depending on the position of the brush on the code plate 4, each switch _{S2-1 , S2-2} ... _S2-6 of switch S2 outputs a six-digit logic signal consisting of 0 or 1 as shown in FIG. Output.

In addition, in FIG. 4, the logical output signal is set to two position states (for example, distance ring 1 is at infinite position ∞,
0.94 m) using the same logic output signal. This is to make the code plate smaller and more dense. Therefore, when the object distance is within 1 m and in the distance range from 1 m or more to infinity, the code signals of the code board and switch _S2 output the same logic signal at two points (distances). Therefore, it is necessary to select the rotation direction of the motor M depending on the actual position of the distance ring. In other words, the distance ring 1 is set within the manual range (there is a range in which the distance measurement accuracy of the automatic focal length value detection device does not output correctly, and this range is manually adjusted by turning the distance ring. , for example, within 1m, and now the distance ring is
Assume that it is set to 0.58m. ) and shoot a subject within the auto range (the range in which the automatic focal length value detection device can accurately measure the distance), for example, when the subject distance is 2m, the distance measurement signal will be sent from line sensor IC ₁ to the subject at 2m. A code signal (011011) representing this is obtained, and this and a code signal as a set distance signal for distance ring 1 are output from the switch group _S2 . Then, both code signals are compared by a comparison circuit in the integrated circuit IC ₂ , and when the two code signals match, the driving of the distance ring 1 is stopped. For this reason, the set distance of the distance ring stops at 0.85 m even though the actual distance to the subject is 2 m, resulting in incorrect distance setting. In order to solve this incorrect setting, the switch _S3 is closed when the range ring 1 is driven within 1 m or if it was set before the power was turned on. And distance ring 1
The object is forcibly rotated from a distance of less than 1 meter toward infinity. When range ring 1 is within 1 meter, the logic output signal of switch _S2 causes the output of 111110 as shown at code address 43 in FIG. That is, terminals 8 to 13 of integrated circuit IC ₂ are connected to terminals TB0, TB1, TB1, as shown in FIGS. 5 and 6.
Pulses TB2, TB3, TB4, and TB5 are output, and since an inverter consisting of a resistor R ₁ and a diode D ₉ is connected to output terminal B, an inverted signal of pulse TB5 is output at output terminal B.

Therefore, when switch _S3 is closed, the signal at terminal 14 is generated by the drive signal forming circuit as shown in FIG.
The waveform of GP ₁₁₁₁₁₀ is output, and this waveform signal causes the terminals A to D to be connected to terminals B and D regardless of the result of the comparison between the distance measurement signal from line sensor IC ₁ and the set distance signal from the code plate. An O signal is always output to the terminal, and a 1 signal is output to the A and C terminals. Therefore, transistors Tr ₇ and Tr ₁₀ of the motor drive circuit (MDC) are turned on, Tr ₈ and Tr ₉ are turned off, and the motor M ₁ rotates toward infinity. Output terminals P ₁ to _{P 5} of the integrated circuit IC ₃ of the ranging circuit, resistors
The circuit consisting of R ₅ , C ₂ to _{C 4} is for threshold adjustment (R ₅ ), peak level maintenance (C ₄ ), and dark current guarantee of integrated circuit IC ₃ (C ₂ , C ₃ ). It is.

The circuit consisting of resistor R ₆ and capacitor C ₁ connected to terminal H of IC ₂ is a power up clear circuit.

_X1 is a known oscillator.

Switch S ₄ connected to terminals OL and SF of IC ₂ is a switch for switching the distance measurement mode of distance measurement circuits IC ₁ to _{IC 3.} By opening and closing switch SW ₄ , terminals OL and SF of the distance measurement circuit are switched. By connecting to ground, the next mode of ) or ) is selected.

By closing SW ₄ , the power switch
By pressing SW ₁ , a distance measurement operation is performed on a subject within the field of view in response to the closing operation of power switch SW ₁ , and the distance ring 1 is driven by motor M to the subject distance to focus. In this operation, power switch SW ₁ also serves as an automatic focus operation switch, and when switch SW ₁ is closed, the camera focuses on the subject at the time when the distance measurement function is activated, and after that, the distance measurement function does not function. do not have. That is, only one focusing operation is performed.

By opening SW ₄ , distance measurement circuit IC ₂ , IC ₃
The sensor continuously outputs a distance measurement signal to the subject, and when the distance to the subject changes, a distance measurement signal is output in response to the change. Therefore, the power switch
When SW ₁ is closed, the distance ring 1 is also driven by the motor M in response to changes in the subject distance and operates to maintain focus at all times. A so-called continuous focus operation is performed.

2 The block symbol U ₁ represents a converter,
By closing power switch SW ₁ for automatic focus adjustment, power is supplied from power supply B ₁ and the reference voltage is
Outputs V _C1 and V _C2 and supplies power to each circuit unit.

3. The motor drive control circuit (MDC) consists of transistors Tr ₁ , Tr ₄ , Tr ₇ , Tr ₁₀ and resistors R ₇ and R ₁₂ , which constitute a normal rotation control circuit (rotation control in the direction of moving the photographing lens toward close range) of the motor M1. , diode _D3 , and transistors _Tr2 , _Tr3 , _Tr8 , _Tr9 , which constitute the motor reversal control circuit (advance control to return the photographing lens toward infinity).
Resistor R ₈ , R ₁₀ , R ₁₁ , diode D ₄ and diode D ₁ , D ₂ that constitute the motor brake circuit
Consists of.

The motor drive control circuit performs forward and reverse operations depending on signals from output terminals A to D of the distance measuring circuit _IC2 .

The battery check circuit (BCC) consists of transistors Tr ₅ , Tr ₁₅ , capacitor C ₁₀ , and resistor R ₂₃ ~
Consists of R ₂₈ , switch SW ₆ , etc. This circuit is explained in the specification of the applicant's utility model registration application No. 114916 of 1981, so the following explanation will be omitted.

MDPC is a motor drive inhibiting circuit, and consists of a capacitor C ₅ , a transistor Tr ₁₂ , resistors R ₁₃ , R ₁₄ , diodes D ₅ , D ₆ , D ₇ , D ₈ and the like. This motor drive prohibition circuit (MDPC) prevents the motor M from being driven immediately after the power switch SW ₁ is turned on, and operates the line sensor IC ₁ and operates the distance measuring circuit IC based on the output signal of the line sensor IC ₁ from the time the power is turned on. _2. This is a circuit that holds approximately 0.1 seconds until IC ₃ is activated. Its operation begins after power switch SW ₁ is closed and capacitor C ₅ starts charging _. The transistor Tr ₁₂ is made conductive until the operation is performed, and the collector of the transistor Tr ₁₂ is connected to the input signal terminal a of the motor drive circuit (MDC).
This prevents the motor M from operating.

The OR circuit consisting of diodes _D5 , _D6 , _D7 , _D8 and resistor _R15 is a sound disabling circuit that logically controls the operation of the sound control circuit (SCC) according to the input state of diodes _D5 to _D8 . Prohibits pronunciation of pronunciation body X ₂ .

That is, when the motor drive circuit (MPC), motor drive prohibition circuit (MDPC), and distance measuring circuit are in operation, a signal is output that prevents the sounding body from producing sound, and when the motor drive prohibition circuit is in operation, a diode is output. by D ₈ , and by diodes D ₅ and D ₆ while the motor is rotating, and by distance measuring circuit IC ₃ and IC _2.
During operation, the transistor Tr ₁₃ of the sound control circuit (SCC) is turned on by the diode D ₇ , and the voltage across the capacitors C ₆ and C ₇ becomes low.
Therefore, transistors Tr ₁₄ , Tr ₁₅ , and Tr ₆ become non-conductive, and the sound generation circuit (SMC) does not operate and the oscillator
X ₂ does not produce sound.

Also, the diodes D ₅ , D ₆ , D ₇ , D ₈ and the resistor R ₁₅
is an OR circuit, so when current stops flowing through each of the diodes _D5 to _D8 , that is, a predetermined period of time has passed after the power is turned on, the distance measurement operation is completed, and the motor M is rotated forward or reverse based on the distance measurement signal. After that, each diode _D5 to _D8 in the OR circuit is de-energized, and the transistor
When Tr ₁₃ becomes non-conductive, capacitors C ₆ and C ₇ start charging through resistors R ₁₆ and R ₁₇ . When the positive terminal voltage of the capacitor _C7 reaches a predetermined voltage, the transistor _Tr15 is connected through the diode _D11 .
Tr ₆ becomes conductive and voltage is applied to the input terminal of the sound generating circuit (SMC). The sound generation circuit is Tr ₁₆ , Tr ₁₇ .
It composes a multivibrator consisting of R ₁₉ , R ₂₀ , R ₂₁ , R ₂₂ , C ₈ , and C ₉ , and when voltage is applied to the input terminal, oscillator X ₂ is oscillated to generate sound.

Switch SW ₅ of the sound control circuit (SCC) is a switch used to stop sound.
As shown in Fig. 2, SW ₅ is the outer case (two points in the figure) of the automatic focusing device (ranging unit S, motor M, code plate 4, circuit and board 8) mounted on the fixed barrel of the interchangeable lens L. (shown with chain lines), and can be opened and closed from the outside.

The sounding element _X2 is fixed to a support frame 9 fixed to the fixed barrel 20 of the first lens barrel described above so as not to impair the sounding function. The support frame 9 is fixed to the rearmost part of the lens barrel in an L-shape, and the sounding body _X2 is fixed to the substantially vertical plane part thereof. With this configuration, you can hear the sound well even when you are surrounded by an outer case, and you can hear the sounds coming from your camera and lens even in crowded places or places where other sounds are present.

Next, a case will be described in which a subject located within the automatic range (for example, 4.7 m) is photographed when the distance set by the distance ring is within the automatic range (for example, 2 m).

When power switch SW ₁ is closed, the converter
Power is supplied to _U1 . The voltage boosted by converter U ₁ is applied to integrated circuits IC ₁ to _{IC 3} ,
The line sensor and distance measuring circuit are activated, and the distance measuring signal and the set distance signal are compared. That is, as described above, the distance to the object is measured by the line sensor, and the measured distance information is input to the integrated circuit IC ₃ to obtain a digital value as a distance measurement signal.
On the other hand, the integrated circuit IC ₂ has a code plate 4 and a brush 5.
The information of the contact switch _S2 formed by a is input as set distance information, and the set distance information and distance measurement information are compared. As mentioned above, the subject distance is 4.7m, so the digital value as the distance measurement signal is (000100) as shown in Figure 4, and the distance set by the distance ring is 2m, so the set distance signal is (011011). Become. Therefore, distance measurement signal > set distance signal, and one signal from output terminals A and C is output from output terminal B,
A 0 signal is output from D. Therefore, transistors Tr ₇ , Tr ₁ , Tr ₄ , and Tr ₁₀ of the drive circuit are turned on, transistors Tr ₈ , Tr ₃ , Tr ₂ , and Tr ₉ are turned off, and current flows in the reverse direction to the motor M, causing the motor to rotate in the reverse direction. do. By the rotation of the motor M,
The distance ring 1 rotates clockwise to shift the set distance value set by the distance return toward infinity. In the process of driving the distance return in this way, when the set distance value reaches 4.7m, the set distance signal becomes (000100).
Therefore, the condition of distance measurement signal = set distance signal is satisfied, and 1 signal is output from output terminals A and B, and 0 signal is output from output terminals C and D. Therefore, transistors Tr ₈ , Tr ₃ , Tr ₄ , and Tr ₁₀ of the drive circuit DDC are turned on.
Tr ₇ , Tr ₁ , Tr ₂ , and Tr ₉ are turned off, and motor M ₁
regenerative braking is applied, the motor stops quickly, and the distance value set by distance ring 10 is 4.7m.
Then, the focus adjustment operation is completed.

Next, a case will be described in which a subject located in the automatic range (for example, 2 m) is photographed in the manual range (for example, 0.67 m) where the distance value set by the distance ring 1 is 1 m or less.

First, when you press the operation button, switch SW ₁
is turned on and converter U ₁ is turned on as in the previous case.
is activated, the integrated circuits IC ₁ to _{IC 3} are energized, and object distance information measured by the line sensor IC ₁ is input to the integrated circuit IC ₃ to obtain a distance measurement signal. On the other hand, the set distance information is set by the switch _S2 , and this information is input to the integrated circuit _IC2 , where the distance measurement signal and the set distance signal are compared. Since the distance value currently set by the distance ring is 0.67m,
The set distance information is (000100) as shown in FIG. 2, and this signal (000100) is compared with the distance measurement signal (currently 2 meters, so it is 011011).
Therefore, the relationship is that distance measurement signal<setting distance signal.
Therefore, a 0 signal is output from the output terminals A and C, and a 1 signal is output from the output terminals B and D, and the drive circuit DDC
Transistors Tr ₂ and Tr ₃ are turned on, motor M ₁ rotates in the opposite direction to the arrow direction, and the distance ring 10
is shifted counterclockwise, that is, toward the short distance side. However, as mentioned above, since the distance value set by the distance ring is within the manual range, the switch _S3 is pressed by the end face 1a of the distance ring 1 and turned on. For this reason, transistors Tr ₁ and Tr ₄ of the drive circuit DDC are turned on and Tr ₂ and Tr ₃ are turned off, and the motor M ₁ rotates in the direction of the arrow, so that the distance ring 1 moves in the direction of infinity ( shifted to the far side). In the process in which the distance ring 1 is driven in the infinite direction, when the distance value set by the distance ring exceeds the manual range, that is, when it reaches 1 m, the switch _S3 changes from the contact point M to the contact point. Switch to A. The control signal of the output line controlled by the circuit SFC disappears. Therefore, after that, the drive circuit
The DDC is controlled by the comparison output, and as mentioned above,
A focusing operation will be performed. That is,
(000000) representing the set distance signal for 1 m and (001101) representing 2 m as the distance measurement signal are compared, and as described above, the motor _M1 rotates in the direction of the arrow, and the distance measurement signal becomes the set distance signal. In other words, when the set value by the distance ring reaches 2m, the motor
Stop rotating at M ₁ and set the distance ring to 2m.
and finishes the focusing operation.

When the above-mentioned distance measurement operation and subsequent focusing operation are completed, the motor M stops rotating, energizing the diodes D ₅ and D ₆ is stopped, the energization from the diode D ₇ is stopped, and the diode is removed from the motor drive prohibition circuit.
Since the current flowing through _D8 also stops, the OR circuit of the sound generation inhibiting circuit logically outputs a high level signal.
This activates the sound generation control circuit (SCC) and causes the sound generation circuit (SMC) to generate periodic sounds.
Notify the operator that the lens L is in focus. This allows the operator to move on to the camera release operation without having to check the focus adjustment state of the object in the viewfinder. Furthermore, the third
In the circuit of the embodiment shown in the figure, the focus completion signal is transmitted by a sound signal, but it _goes without saying that the sound signal may be changed to a light emission signal. The signal line n connected to the terminal is connected to a known light emitting circuit, and the sounding body X ₂ is replaced with a light emitting body. As a result, when the focus is completed, the light emitting body repeats blinking in accordance with the oscillation cycle of the vibrator, and continues to emit light and blink until it is time for the capacitor _C6 to complete charging.

FIG. 7 shows a battery case 10 which is detachably attached to the interchangeable lens of the embodiment shown in FIG. Holes 10a and 10b are provided for connection to electrodes 11a and 11b provided in the battery case housing.

A recess 10c shown in FIG. 7 is formed on the back surface of the battery case 10. One end surface of this recessed portion 10C is open, and the other end surface is formed of a conductive member. The battery case 10 in FIG. 7 is installed in the case housing portion of the lens barrel with the switch box 21 of _the switch S ₄ as a guide, as shown by the two-dot chain line in FIG. _2. Constructed to be wearable. When installing the battery case 10, as shown in FIGS. 7a and 7b, an engagement hole 10L is provided on the back side of the battery case for engagement of the lock claw 30, and the recess 10C of the battery case 10 is provided. The conductive portion 10C ₂ comes into contact with the contacts S _4-a and S _4-b of the servo operation switch S ₄ shown in FIG. 3, and the distance measuring circuit system is switched to the servo operation system as described above.

The lock claw 30 is attached to the fixed barrel 2 of the interchangeable lens barrel.
0 with a screw 32, and is biased counterclockwise by a spring 31.
When the battery 10 is stored in the battery storage portion of the outer frame shown by the two-dot chain line in the figure, the lock pawl 30 and the engagement hole 10l engage, and the battery case 10 is locked.

To remove the battery case, push the other end 30a of the lock claw in a direction opposite to the spring 31, and the case 10 will be unlocked and the case can be taken out. The circuit configuration and explanation for switching to the servo operating system are described in the aforementioned Japanese Patent Application No. 4-22906.

In the circuit shown in Figure 3, the servo operation switch
If SW ₄ is left open, line sensor IC ₁ , distance measurement circuit IC ₂ , and IC ₃ will operate only once as the power switch SW ₁ closes, and the shooting lens will focus on the subject captured. A focusing operation is performed, and the distance measuring circuit stops when one cycle of calculation operations is completed. The operation of opening switch SW ₄ corresponds to the one-more-focus mode of the semi-auto mode described in the specification of Japanese Patent Application No. 54-22906. Furthermore, when the switch SW ₄ in FIG. 3 is closed by the battery case 10, after the power switch SW ₁ is closed, if the subject distance changes, the line sensor IC ₁ .
The distance measuring circuits IC ₂ and IC ₃ move the distance ring 1 in response to changes in the object distance, thereby performing continuous focusing operations. This continuous focusing operation is based on the aforementioned patent application No. 54-22906.
This corresponds to the continuous mode of the fully automatic mode in the specification.

When performing the One More Focus mode using the circuit shown in Figure 3, the recessed portion of the battery case 10 is provided with an extra dimension in the axial direction (longitudinal direction), so that the switch SW ₄ will not close even if the battery case is attached to the lens. Alternatively, the switch SW ₄ may be placed elsewhere and the terminals OL and SF of the circuit IC ₂ may be connected to ground manually.

Next, the case of using an external power source will be explained.
The explanation of the embodiment shown in FIG. 2 relates to an embodiment of a so-called internal power source in which a battery case 10 is housed in an interchangeable lens L. However, when an internal power source is provided in an interchangeable lens, the shape of the lens portion becomes large, which causes inconvenience in holding, increases weight, and requires a large-capacity power source to be provided on the interchangeable lens. For this purpose, the automatic focusing device on the interchangeable lens may sometimes depend on an external power source. Furthermore, when an external power source is used as the power source, it is convenient to switch between the aforementioned focusing modes (one-more mode and continuous mode).

FIG. 7 shows an embodiment of the external power supply case. When the external power supply case is housed in the exterior case, the positive electrode of the external power supply case comes into contact with the external power supply positive electrode 13 shown in FIG. The negative electrode contacts the negative electrode 11b in FIG. A recess is also provided on the back of the external power supply case to escape the box 21 of switch SW ₄ , and the axial dimension of the recess is designed as appropriate depending on the case.
Allow SW ₄ to open or close. As a result, switching between the one-more mode and the continuous mode described above can be performed by selecting the battery case.

As described above, the present invention provides an interchangeable lens equipped with an automatic focusing device that enables automatic focusing photography and automatically selects an appropriate automatic focusing mode when a battery case is attached. It is something.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a distance ring 1 and a code plate 4 for detecting set distance information of a distance ring of a photographing lens used in an embodiment of the present invention. FIG. 2 is a perspective view in which the embodiment of the present invention is applied to an interchangeable lens for a camera, and the distance measuring device S for automatic focusing, the code plate 4, the motor M, etc. are mounted on the lens barrel of the interchangeable lens. . FIG. 3 is a circuit diagram of an embodiment of the present invention. FIG. 4 is a diagram showing an output signal at each setting position in which the setting (or adjustment) distance information of the distance ring is converted into a binary signal. FIG. 5 is an explanatory diagram of the switch group S _2-1 ...S _2-6 , the output terminal of the integrated circuit IC ₂ , and the drive signal forming circuit shown in FIG. FIG. 6 is a waveform diagram of output pulses from each terminal shown in FIG. 5. Figure 7 shows the battery case of the circuit of Figure 3;
Figure 7a shows Case 1 with the lens stored in the case 1.
FIG. 7b is a view of the case viewed from the back, and FIG. 7c is a partial sectional view showing the case 10 in a locked state. MDC...Motor drive circuit, DSFC...Drive signal forming circuit, MDPC...Motor drive prohibition circuit, BCC...Battery check circuit, SCC...
...Sound control circuit, SMC...Sound generation circuit.

Claims (1)

[Claims] 1. In an interchangeable lens that has an automatic focusing device that moves and controls a photographing lens built into the interchangeable lens to a focusing position, and also has a removable battery case that stores a battery, the automatic focusing device A focus control circuit is provided that can select between a first autofocus mode in which focusing operations are prohibited from subsequent focusing operations, and a second autofocus mode in which focusing operations are performed continuously. A selection circuit for selecting a mode is provided, and further comes into contact with the battery case when the battery case is installed;
An interchangeable lens equipped with an automatic focusing device, characterized in that a switch member is provided for activating the selection circuit to select the second automatic focusing mode.