JP2002221653A - Zoom device for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect whether or not a zoom position is moved at low cost with low current consumption. SOLUTION: This zoom device is equipped with a zoom driving means M1 driving a zoom lens barrel, a zoom position detection part M2 detecting the absolute position of the zoom lens barrel interlocked with zoom driving by the driving means M1, an interruption detection part M3 connected to the detection part M2 and detecting the information of the detection part M2 by interruption, and a control means M4 judging zoom position information according to the setting of the detection part M3 and output from the detection part M3 and also controlling the driving means M1. When judging that the position of the zoom lens barrel confirmed previous time is different from the zoom position at this time in the case of performing processing to reconfirm the position of the zoom lens barrel by the control means M4, the zoom position is restored to the previously set absolute position such as a zoom wide end position once.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera zoom device having a mechanism for detecting that a lens position has been moved under the influence of an external force.

[0002]

2. Description of the Related Art Generally, in a camera provided with an extension mechanism for performing zooming by extending the lens barrel from the camera body, the lens barrel is extended from the camera body, and the front end of the lens barrel is moved toward the camera body. When an external force or impact is applied, the lens barrel is retracted into the main body by the operation of a clutch or the like to prevent damage to the lens barrel and the drive mechanism of the lens barrel. I have.

However, when an external force is applied to the front end of the lens barrel, the lens barrel moves and the zoom lens moves from the stored position of the zoom lens (hereinafter referred to as "zoom position"). There is. If zooming is performed in such a state, particularly when the lens position is detected by a relative amount, there is a disadvantage that the zoom position after the movement is erroneously detected, which hinders camera control.

To cope with this, for example, Japanese Patent Laid-Open No. 9-23
In Japanese Patent Application Publication No. 0206, a zoom code (absolute position encoding) for repeating a detection area and a non-detection area is provided in a zoom position detection mechanism, and even if an external force is applied to move the zoom position, the subsequent zoom is performed. A technique has been disclosed in which a zoom position can be determined based on zoom code information during driving.

In Japanese Patent Application Laid-Open No. 10-142482, a zoom lens is determined by using a PI (photo interrupter) and judging a zoom position in a state of a received signal at an "H" level or an "L" level. A technique has been disclosed in which, when is moved and it is determined that the zoom position is not at a predetermined position, the zoom position is reset.

[0006]

SUMMARY OF THE INVENTION However, Japanese Patent Application Laid-Open No. Hei 9-2
In the technology disclosed in Japanese Patent No. 30206, the zoom position is determined based on the zoom code information, so that a long detection area is required inside the lens barrel, and a sliding brush is used. , Resulting in high costs.

In the technique disclosed in Japanese Patent Application Laid-Open No. H10-142482, the zoom position is determined by detecting the "H" level signal and the "L" level signal of the PI signal. Before the zoom position detection control, the PI signal becomes “H” due to an external force applied to the front end of the lens barrel.
In the case of a camera having a mechanical mechanism in which the zoom position moves from a predetermined position while changing from “L” to “H”, there is a disadvantage that the zoom position after the movement is erroneously determined.

As a countermeasure, it is conceivable to monitor the zoom position while keeping the PI signal ON, but there is a problem that the current consumption of the entire camera increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and is directed to a camera capable of accurately detecting whether or not a zoom position has been moved at low cost and with low current consumption. It is an object to provide a zoom device.

[0010]

In order to achieve the above object, a camera zoom apparatus according to the present invention comprises a zoom driving means for driving a zoom lens, and an absolute position signal of the zoom lens in conjunction with the driving of the zoom lens. A zoom position detecting means, an interrupt detecting means connected to the zoom position detecting means for detecting a zoom position detecting signal by interrupt processing, and the zoom lens being moved by an external force by the detection of the interrupt detecting means. Determining that the zoom lens has been moved by interrupt processing.

In this case, preferably, the interrupt detecting means has a noise removing means.

More preferably, the zoom lens is returned to a predetermined position when it is determined by the determining means that the zoom lens has been moved by an external force.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, as a function of monitoring zoom position information, as shown in a conceptual diagram of FIG. 1A, a zoom driving means M1 for driving a zoom lens barrel.
And a zoom position detecting section M2 for detecting an absolute position of the zoom lens barrel in conjunction with zoom driving of the zoom driving means M1.
An interrupt detection unit M3 connected to the zoom position detection unit M2 and detecting information of the zoom position detection unit M2 by interruption, and a zoom position based on the settings of the interruption detection unit M3 and the output from the interruption detection unit M3. Control means M4 for judging information and controlling the zoom drive means M1
And

According to such a configuration, the control means M4
However, when reconfirming the position of the zoom lens barrel,
It is determined by an interrupt process that the position is different from the position of the zoom lens barrel confirmed last time. Since the position of the zoom lens barrel is constantly monitored, no erroneous determination is made even if the zoom lens barrel is moved by an external force.

As another function of monitoring the zoom position information, as shown in FIG. 1B, a zoom driving means M1 for driving a zoom lens barrel and a zoom driving means M1
The zoom position detecting unit M2 detects the absolute position of the zoom lens barrel in conjunction with the drive of the zoom lens unit, the noise removing unit M5 that removes noise from information from the zoom position detecting unit M2, and the noise removing unit M5. An interrupt detection unit M3 that detects information of the cage zoom position detection unit M2 by interruption, a setting of the interruption detection unit M3, a setting of a chattering noise removal time processed by the noise removal unit M5, and a signal from the interruption detection unit M3. A control unit M4 for determining the zoom position information based on the output and controlling the zoom driving unit M1.

In such a configuration, when the control means M4 performs the reconfirmation processing of the position of the zoom lens barrel, the control means M4 determines that the position is different from the previously confirmed position of the zoom lens barrel by interruption processing. Since the position of the zoom lens barrel is constantly monitored, there is no erroneous determination even if the zoom lens barrel is moved by an external force. Further, since chattering noise is removed from the signal output from the zoom position detection unit M2 by the noise removal unit M5, the absolute position of the zoom lens barrel is detected using a switch having mechanical contacts. In addition, erroneous determination due to chattering noise or static electricity is prevented.

An embodiment of the present invention will be described below with reference to the drawings. 2 to 15 show a first embodiment of the present invention. FIG. 2 is a schematic configuration diagram of a control system of the camera, FIG. 3 is a functional block diagram of interrupt detection means, FIG. 4 is a longitudinal sectional view of a zoom lens barrel in a zoom retracted state, and FIG. 5 is a zoom lens barrel in a zoom wide state. FIG. 6 is a longitudinal sectional view of the zoom lens barrel in the zoom telephoto state.

In FIG. 2, reference numeral 1 denotes a camera body equipped with an auto-zoom function (hereinafter referred to as "camera body"). Reference numeral 2 denotes a retractable zoom lens barrel provided on the front of the camera body. 1, a control unit 30 for controlling the operation of the entire camera is built in. In addition, the zoom lens barrel 2 according to the present embodiment moves from the retracted (storage) state, which is a non-photographing state stored in the camera body 1, to a zoom wide position, which is the shortest focal length position in a shooting preparation state set up. It is possible to move back and forth to the end position (W) and further to the zoom tele end position (T) which is the longest focal length position in the shooting state.

First, the configuration of the zoom lens barrel 2 will be described with reference to FIGS. Zoom lens barrel 2
Is a fixed frame 3 that is fixed directly or indirectly to the camera body 1, a rotating frame 4 that is held in the fixed frame 3 so as to rotate and move forward and backward, and is fitted into the rotating frame 4 and rotated. A moving frame 5 connected to the frame 4 and the fixed frame 3 and capable of moving straight in the direction of the optical axis O; a cam frame 6 rotatably and advancing and retracting within the moving frame 5; A first group lens frame 7 fitted into the first lens group 6 and capable of moving straight in the direction of the optical axis O, and a cam frame 6 fitted in the first group lens frame 7 in the direction of the optical axis O.
A float key (straight ring) 8 that moves integrally with the
A second group lens frame 9 which is fitted into the float key 8 and is able to move straight in the direction of the optical axis O, and is held in the float key 8 at a rear portion of the second group lens frame 9 and is able to move straight in the direction of the optical axis O And a third group lens frame 10.

The third group lens frame 10 is provided with a cam follower 11. The third group lens frame 10 is moved in the direction of the optical axis O with respect to the cam frame 6 via the cam follower 11 and the float key 8. It is supported so that it can go straight along.
In each of the lens frames 7, 9, and 10, a zoom first group lens 12, a zoom second group lens 13, and a zoom third group lens 14 are fixedly provided as a photographing zoom lens optical system. The zoom second group lens 13 is an auto-focus lens, and focus is performed by moving the zoom second group lens 13 along the optical axis. Further, the zoom magnification can be changed by moving the first zoom lens 12 and the third zoom lens 14 relatively.

A claw portion 5a is formed on the outer periphery of the rear end of the movable frame 5. On the other hand, the claw portion 5a is engaged with the inner periphery of the fixed frame 3 and allows the rectilinear movement. Groove 3a
Are formed. A tele end switch shaft portion 15a and a wide end switch shaft portion 15b are arranged on the outer periphery of the rectilinear groove 3a. As shown in FIG. 6, the tele end switch shaft portion 15a is disposed at a position where the tele end switch shaft portion 15a is engaged with the claw portion 5a and pushed up when the zoom lens barrel 2 is at the zoom tele end position. As shown in FIG. 5, the wide-end switch shaft 15b is disposed at a position where the wide-end switch shaft 15b is engaged with the claw 5a and pushed up when the zoom lens barrel 2 is at the zoom wide end position.

FIGS. 7 and 8 show switch shaft portions 15a,
15b shows a switch circuit 20 connected in series. This switch circuit 20 constitutes a part of a zoom position detecting means 36 described later. Since the configuration of the switch circuit 20 is common to the switch shaft portions 15a and 15b at both ends, the switch shaft portions 15a and 15b at the respective ends will be hereinafter collectively referred to as the switch shaft portions 15.

The switch section 21 provided in the switch circuit 20 includes a movable switch piece 21a and a fixed switch piece 21b.
The end switch shaft 15 is connected to the movable switch piece 21a. This end switch shaft 15
Is constantly depressed in the inner circumferential direction of the fixed frame 3 by the pressing force of the movable switch piece 21a. As shown in FIG.
The claw portion 5 formed on the movable frame 5 by the movable switch piece 21a
a, the movable switch piece 21a
The fixed switch piece 21b and the fixed switch piece 21b are closed. On the other hand, as shown in FIG. 8, when the movable switch piece 21a is engaged with the claw portion 5a, the movable switch piece 21a is pushed up and opened.

The movable switch piece 21a is connected to the main CPU 3
1 and connected to the power supply battery 22 via a resistor R1. On the other hand, the fixed switch piece 21b is connected to the GND side. Therefore, when the zoom lens barrel 2 is in the movable range between the zoom retracted position (see FIG. 4) or the zoom wide end position (W) and the zoom tele end position (T), the switch unit 21 is closed. Therefore, the potential of the interrupt port of the main CPU 31 becomes equivalent to GND, and an "L" level zoom position signal is detected at this interrupt port. On the other hand, when the switch unit 21 is open (the state shown in FIG. 8), the “H” level zoom position signal is detected at the interrupt port of the main CPU 31 by the pull-up voltage from the power supply battery 22.

FIG. 14 shows the relationship between the extension amount of the zoom lens barrel 2 and the zoom position signal detected by the main CPU 31 at the zoom rotation angle. As shown in the figure, when the zoom lens barrel 2 is at the zoom wide end position (W) or the zoom tele end position (T), the main CPU 31 detects an "H" level zoom position signal. In this state, an "L" level zoom position signal is detected. Therefore, when the main CPU 31 detects the "H" level zoom position signal, the zoom position is set to the absolute position (zoom wide end position (W) or zoom tele end position (T)).
Can be determined.

Next, the configuration of the control unit 30 built in the camera body 1 will be described. As shown in FIG. 2, the control unit 30 has a built-in main CPU 31 for controlling the entire camera,
A power supply circuit 32 for supplying power to each circuit of the camera including the main CPU 31 for the PU 31, a power switch, a release switch, a zoom up switch, a zoom down switch, a rear cover switch, a date display function switch, and a camera mode selection function switch. , Self mode switch,
A switch section 33 composed of switches such as an imprint setting switch, a feed motor drive circuit 34 for feeding a film,
A zoom drive unit 35 that drives the zoom lens (the zoom first group lens 12 and the zoom third group lens 14) for zooming, and the absolute position of the zoom lens barrel 2 (zoom wide end position (W) or A zoom position detecting means 36 for detecting a zoom tele end position (T)), an LCD display circuit 37 for controlling a display operation of a liquid crystal (LCD) for displaying the number of frames and a camera mode, etc., a photometric unit 38 for measuring the brightness of a subject, AF for moving the zoom second group lens 13 having the function of a focus lens to a position where focus is achieved
A lens drive circuit 39, a shutter control circuit 40 for controlling shutter blades in a shutter unit (not shown), a strobe light emission control circuit 41 for controlling strobe light emission, a charging circuit 42 for accumulating energy for emitting strobe light, A distance measuring unit 43 for measuring the distance to the subject, an operation clock 44 having an oscillator having a predetermined frequency (8 Mz in the present embodiment), and the like are connected.

Further, as shown in FIG.
Includes an interrupt detecting means 31 having an interrupt detecting function.
a is provided. This interrupt detecting means 31a
It comprises an interrupt setting section 51, a noise removing section 52, an interrupt determining section 53, an execution control section 54, and the like.

The execution control unit 54 receives the interrupt occurrence signal from the interrupt determination unit 53, selects whether to enable or disable the interrupt, and changes the zoom position signal from "H" to "H".
A setting is made to select which edge of the falling edge of “L” or the rising edge of “L” → “H” is to be detected.
Of the chattering noise generated by the opening / closing of, and sends a command to the interrupt setting unit 51 and the noise removing unit 52.

For example, as shown in Case 1 of FIG. 15B, when the previous zoom position (Z2) is the zoom wide end position (W), an "H" level zoom position signal is detected. Therefore, whether the zoom position has been moved
When trying to move the zoom lens barrel 2 this time,
Since the determination can be made by checking whether or not the zoom position signal of the “L” level is detected, it is set so that the edge in the falling direction is detected. On the other hand, as shown in Case 2, when the previous zoom position (Z1) is between the zoom wide end position (W) and the zoom tele end position (T),
Since the "L" level zoom position signal is detected, whether the zoom position has been moved depends on whether the "H" level zoom position signal has been detected this time when the zoom lens barrel 2 is to be moved. Can be determined by examining, so that an edge in the rising direction is set to be detected.

The interrupt setting section 51 sets permission / non-permission of interrupt processing in accordance with an instruction from the execution control section 54,
And the detection direction (rising edge, falling edge, or both edges) of the interrupt edge is set. Interrupt setting unit 51
By setting the edge detection direction, it is possible to detect whether or not the zoom position has been moved by an external force when trying to move the zoom lens barrel 2 in the interrupt determination unit 53 described later. Can be.

The noise elimination unit 52 calculates the zoom position signal output from the zoom position detection unit 36 according to the chattering noise elimination time set by the execution control unit 54.
The chattering noise generated in the switch unit 21 is removed. Since chattering noise is removed from the zoom position signal, the interrupt determination unit 53 that determines an interrupt condition based on the zoom position signal can detect the edge direction (rising or falling) with high accuracy.

The interrupt determining unit 53 includes an interrupt setting unit 5
An interrupt is generated based on the interrupt condition set in step 1 (the condition in which edge is detected or whether both edges are detected) and the zoom position signal output from the noise removing unit 52 after chattering noise removal. It is checked whether or not it has occurred, that is, whether or not the zoom lens barrel 2 has been moved. Then, if the interrupt setting condition is satisfied, an interrupt signal is output to the execution control unit 54.

The determination conditions processed by the interrupt determination unit 53 are, for example, in case 1 of FIG. 15B, the previous position (Z2) of the zoom lens barrel 2 is the zoom wide end position (W), Since the zoom position signal of the “H” level is detected, this time the falling direction (“H” → “L”)
Edge detection becomes an interrupt condition. In case 2, the position (Z1) of the previous zoom lens barrel 2 is located at an intermediate position (Z3) between the zoom tele end position (T) and the zoom wide end position (W), and the zoom at the "L" level is set. Since the position signal is detected, this time the rising direction (“L” →
The “H”) edge detection is an interrupt condition.

In case 1 shown in FIG. 3, when the zoom lens barrel 2 is to be moved this time, an "L" level zoom position signal, that is, a falling edge is detected, and the interrupt condition is satisfied. . Similarly, in case 2, when the user tries to move the zoom lens barrel 2 this time,
The “H” level zoom position signal, that is, the rising edge is detected, and the interrupt condition is satisfied.

Next, the control operation of the entire camera, which is processed by the control unit 30 shown in FIG. 2, will be described with reference to the flowcharts shown in FIGS.

In this flowchart, first, when a power supply battery is loaded in the power supply circuit 32 in step S1, data and flags stored in the RAM incorporated in the main CPU 31 are initialized in step S2. Subsequently, in step S3, a process of performing a battery check is performed.

If there is no problem in "battery check",
Proceeding to step S4, the state of the power switch provided in the switch unit 33 is checked. And the power switch is ON
If so, the process proceeds to step S5, where the zoom lens barrel 2 is set up at the zoom wide end position (W). When the power switch is OFF, the zoom lens barrel 2 is in the retracted position (see FIG. 4) in the non-shooting state stored in the camera body 1 and is extended forward when the power switch is turned ON. Is set to the zoom wide end position (W), which is the shortest focal length position in the shooting preparation state (see FIG. 5). On the other hand, when the power switch is OFF, the zoom lens barrel 2 is not operated, and step S6 is performed.
Jump to

In step S6, the display timer is started. In step S7, the state of the power switch provided in the switch unit 33 is checked again. If the power switch is off, the process branches to step S31. If the power switch is on, the process proceeds to step S8.
Proceed to.

In step S31, the zoom lens barrel 2 is returned from the zoom wide end position to the collapsed position, and then the process proceeds to step S32, where the LCD display circuit 37 is turned off, and the process proceeds to step S33. Then, the main CPU 31 is stopped, and the process returns to step S2. As a result, the operation clock 44 having the oscillator having the predetermined frequency is stopped.

On the other hand, in step S8, it is checked whether four minutes have passed since the power switch provided in the switch section 33 was turned on.
Branch to 2. If four minutes have not elapsed, the process proceeds to step S9, where the LCD display circuit 37 is turned on to perform liquid crystal display, and then proceeds to step S10.

In step S10, it is checked whether or not the flash has been charged. If the charging has not been completed, the process proceeds to step S11, in which the strobe is charged. After the charging is completed, the process proceeds to step S12. If the charging of the strobe has been completed, the process jumps from step S10 to step S12.

When proceeding to step S12, step S1
In step S13, the state of the rear lid is checked based on the output signal of the rear lid switch provided in the switch unit 33. Then, when the rear lid changes from the open state to the closed state, the process branches to step S36 to perform a battery check. After performing idle film feeding in step S37, the process returns to step S6.

When the rear cover is opened from the closed state, the process branches from step S13 to step S41 to check the battery, and proceeds to step S42 to indicate whether or not the film has been rewound. Flag RWE
DF is cleared (RWEDF = 0), and the process returns to step S6.

On the other hand, when the rear lid is kept closed,
Proceeding to step S14, the value of the flag RWEDF is checked. This flag RWEDF is set when rewinding has been completed (RWEDF = 1), and cleared when rewinding has not been completed (RWEDF = 0). And
Film rewinding has been completed (RWEDF = 1)
Returns to step S7, and if the film has not been rewound (RWEDF = 0), the process returns to step S1.
Go to 5.

At step S15, the switch unit 33
The state of the release switch having a two-stage structure of 1R and 2R, which is provided in
If so, the process branches to step S46. If the release switch is ON, the process proceeds to step S16.

When the flow branches to step S46, the state of the zoom-up switch and the zoom-down switch provided in the switch section 33 is checked. If zooming is not performed, the flow returns to step S7. If one of the zoom-up switch and the zoom-down switch is ON, the process proceeds to step S47, where a battery check is performed.
Subsequently, in step S48, the zoom drive unit 35 is driven to perform zoom control processing, and the process returns to step S6.

This zoom control processing is performed according to a zoom control routine shown in FIG. In this routine, when it is determined that the zoom position at the time of performing the zoom operation is not the predetermined position, that is, when it is determined that the zoom position has been moved by an external force, the zoom position is determined so as not to break the zoom. The collapsing operation with the drive voltage lowered is performed, and once to the zoom wide end position (W),
Return the zoom lens barrel 2 to assure the zoom position.
The zoom control routine will be described later.

On the other hand, when the release switch is determined to be ON and the process proceeds to step S16, a battery check is performed.
Proceed to step S17 to execute zoom position determination processing,
Proceed to step S18.

The zoom position determination processing is performed according to a zoom position determination processing routine shown in FIG. And
In this routine, when it is determined that the zoom position at the time of performing the zoom operation is not the predetermined position, the collapsing operation in which the drive voltage for unfixed zoom position is reduced is performed so as not to break the zoom, and the zoom wide end position ( Returning to W), the zoom lens barrel 2 is returned once to guarantee the zoom position. still,
This zoom position determination processing routine will be described later.

Next, when the flow advances to step S18, the release switch 1R is turned on, and the light meter 38 and the distance meter 43 are turned on.
In step S19, the release switch 2R is turned ON and AF is performed.
The drive of the AF lens is controlled by the lens drive circuit 39, and the process proceeds to step S20, where the shutter control circuit 40 controls the shutter speed.

When the photographing is completed, step S2
Then, the film winding control is performed, and step S
At 22, it is determined whether or not the film has ended based on whether or not the film end has been reached. If the film end has not been reached, the process returns to step S6. If the film end has been reached, the process proceeds to step S23, where the flag RWEDF is set (RWEDF = 1), and the film is rewound. Return to

In this case, if it is determined in step S18 that strobe light emission is necessary based on the output measured by the photometry unit 38, the strobe light is synchronized in the shutter control performed in step S20. Then, the strobe light emission control circuit 41 is driven. Further, from the stop state of step S33, the operation clock 44 is restarted by an interruption by each switch such as a power switch, a rear cover switch, a zoom up switch and a zoom down switch provided in the switch unit 33, and thereby the main operation is started. The CPU 31 is activated, the process proceeds to step S2, and the operation of the camera is restarted.

Next, zoom control performed in step S48 of the main flowchart of FIG. 10 will be described with reference to FIG.
A description will be given according to the zoom control routine shown in FIG.

First, in step S51, the zoom position signal output from the zoom position detecting means 36 is compared with an interrupt condition, and whether or not an interrupt has occurred, that is, an external force applied to the front end of the zoom lens barrel 2 toward the camera body 1 is determined. It is checked whether or not the zoom position has been moved by the application of the like. When an interruption occurs, that is, when it is determined that the zoom lens barrel 2 has been moved by an external force,
The process proceeds to step S52, and if there is no interruption, the process branches to step S55.

When it is determined that the zoom position has been moved and the process proceeds to step S52, a retracting operation is performed with the drive voltage for unfixed zoom position lowered so as not to break the zoom. In step S53, the zoom lens barrel 2 is moved. Is once returned to the zoom wide end position (see FIG. 5), and the zoom position is reset to the absolute position. Here, since the zoom is forcibly reset once, the zooming control is performed when the zoom switch is turned on next time.

Thereafter, the flow advances to step S54 to perform initial setting of the zoom position detection, and prepares for the next interruption determination, and then exits the routine.

On the other hand, if it is determined that the zoom position has not been moved, and the process branches from step S51 to step S55, normal control is performed in which zoom driving is performed only during the time when the zoom switch is ON. S54
Proceed to. In this case, if the zoom position has already reached the zoom telephoto end position (T) or the zoom wide end position (W), the process directly proceeds to step S54. The initial setting of the zoom position detection executed in step S54 will be described later.

Next, the zoom position determination processing performed in step S17 of the main flowchart in FIG.
A description will be given according to the zoom position determination processing routine shown in FIG.

In this routine, first, at step S61
Then, the zoom position signal output from the zoom position detecting means 36 is compared with the interrupt condition, and whether or not an interrupt has occurred, that is, an external force or the like directed toward the camera body 1 is applied to the front end of the zoom lens barrel 2 so that the zoom position Check if has been moved. If there is an interrupt, that is, if it is determined that the zoom lens barrel 2 has been moved by an external force, the process proceeds to step S62, and if there is no interrupt, the process exits the routine.

If it is determined that the zoom position has been moved and the process proceeds to step S62, a retracting operation is performed in which the drive voltage for unfixed zoom position has been reduced so as not to break the zoom. 2 is returned to the zoom wide end position (W), and the zoom position is once again set to the absolute value. Next, the process proceeds to step S64 to perform initial setting of zoom position detection, and prepares for the next interruption determination, and then exits the routine.

The initial setting of the zoom position detection executed in step S54 of FIG. 11 and step S64 of FIG. 12 is processed according to the zoom position detection initial setting routine shown in FIG.

In this routine, first, step S71
Then, the data relating to the zoom interrupt stored in the RAM is initialized, the port setting relating to the zoom interrupt is initialized in the following step S72, and the interrupt execution setting and the noise chattering elimination time are initialized in step S73.

The flow advances to step S74 to read the current zoom position information, and the flow advances to step S75 to check the current state of the zoom lens barrel 2. When the zoom lens barrel 2 is at the zoom wide end position (W) or the zoom tele end position (T), an "H" level zoom position signal is detected. L "
A level zoom position signal is detected (see FIG. 14).

In step S75, when the current zoom position signal is at the "H" level (the state of FIG. 15A),
Since it is desired to detect a change to the “L” level, step S7
The process proceeds to step S6, where edge detection in the falling direction is set as an interrupt condition, and the routine exits. On the other hand, when the current zoom position signal is at the "L" level (state (a) or (c) in FIG. 16), it is desired to detect a change to the "H" level, and the process branches to step S77 to start up. The edge detection in the direction is set as an interrupt condition, and the routine exits.

In the present embodiment, after the interruption is detected, the zoom lens barrel 2 is finally moved to the zoom wide end position (W), which is the absolute position, to set the initial value. The zoom telephoto end position (T) or the zoom retracted position may be set as an absolute position, and once moved to this position to set an initial value. Further, the absolute position may be set to the retracted position, and the initial position may be set to the zoom wide end position (W) after returning to the retracted position once.

The noise elimination unit 52 is connected to the main CPU 31.
The noise removing unit 52 is provided in the main CP.
It may be a hard character using an external capacitor of U31.

Further, in the present embodiment, as shown in case 3 of FIG. 15B, an external force or the like directed toward the camera body 1 is applied to the front end of the zoom lens barrel 3 to move the zoom position. When the zoom position is initially at the position (Z1) and then the zoom position is pressed to the position (Z3) by an external force, the interrupt detection condition is changed to the rising direction ("L" → "") at the position (Z1). H)), and the falling direction (“H” →
The edge detection is set to "L"), and the edge is detected at the position (Z3) in the rising direction ("L" → "H"). Therefore, each time the edge detection direction is switched, the interrupt condition is reset, so that even in such a case, it is possible to accurately detect that the zoom position has been moved.

FIGS. 16 and 17 show a second embodiment of the present invention. As shown in FIG. 16, in the present embodiment,
A date setting circuit 61 that can set and manage a date (date and time) and a storage unit 62 such as a non-volatile memory that can store date information are added to the control unit 30, and the date setting circuit 61 and the storage unit 62 are stored by the main CPU 31. It is intended to be controlled.

By adding the date setting circuit 61 and the storage means 62 to the control unit 30, when the main CPU 31 performs the zoom position determination processing, the camera may fail due to the movement of the zoom position.
The history of the date when the impact was applied to the zoom lens barrel 2 can be left.

This date information is read when executing the zoom position determination processing routine shown in FIG. In this routine, first, in step S81, as in step S61 of FIG. 12, the zoom position signal is compared with the interrupt condition, and whether or not there is an interrupt, that is, the external force toward the camera body 1 at the front end of the zoom lens barrel 2 is determined. It is checked whether or not the zoom position has been moved by the application of the like. And
If there is an interrupt, the process proceeds to step S82, and if there is no interrupt, the process exits the routine.

At step S82, the date setting circuit 6
1 is read out to the RAM in the main CPU 31, and the date data is stored in the storage means 62 in step S83.

Then, the process proceeds to a step S84. Steps S84 to S86 correspond to steps S62 to S64 in FIG.
Therefore, the description is omitted.

As described above, according to the present embodiment, when the camera breaks down due to the movement of the zoom position, or the date when the impact was applied to the zoom lens barrel 2 remains in the history, the failure detection and It can also be used as a failure history. The processing performed in steps S82 and S83 may be performed in a zoom position detection initial setting routine shown in FIG.

[Supplementary Note] As described above, according to the present embodiment, the following configuration can be obtained. (1) A zoom driving means for driving the zoom lens, a lens barrel position detecting means for detecting an absolute position signal of the zoom lens in conjunction with the driving of the zoom lens, and a lens barrel position detecting means. A zoom device for a camera, comprising: interrupt detection means for detecting a zoom position detection signal by interrupt processing; and determination means for determining that the zoom lens has been moved by an external force by detection of the interrupt detection means.

(2) In (1), date setting means,
Storage means, wherein date data is stored in the storage means when the zoom position is not at the predetermined position.

(3) In (1) and (2), when the judgment means judges that the zoom lens has been moved by an external force, the zoom lens is returned to a predetermined position.

(4) In (3), the predetermined position is:
It is a retracted position of the zoom lens.

(5) In (3), the predetermined position is:
It is a zoom wide end position after returning the zoom lens to the retracted position.

[0079]

As described above, according to the present invention, it is possible to always detect that the zoom position has been moved at low cost and with low current consumption, thereby preventing erroneous determination of the zoom position. can do.

Further, when it is detected that the zoom position has been moved, the zoom position is moved to a position where the zoom position can be guaranteed, so that reliable control and photographing can always be performed.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a control system according to a first embodiment.

FIG. 2 is a schematic configuration diagram of a control system of the camera.

FIG. 3 is a functional block diagram of the interrupt detection unit.

FIG. 4 is a longitudinal sectional view of the zoom lens barrel in the collapsed state.

FIG. 5 is a longitudinal sectional view of the zoom lens barrel in the zoom wide state;

FIG. 6 is a vertical sectional view of the zoom lens barrel in the zoom telephoto state;

FIG. 7 is an explanatory diagram of the switch circuit in the closed state.

FIG. 8 is a circuit diagram of the switch circuit in the open state;

FIG. 9 is a flowchart showing a control operation routine of the whole camera (part 1);

FIG. 10 is a flowchart showing a control operation routine of the whole camera (part 2);

FIG. 11 is a flowchart showing a zoom control routine.

FIG. 12 is a flowchart showing a zoom position determination processing routine;

FIG. 13 is a flowchart showing a zoom position detection initial setting routine;

FIG. 14 is an explanatory diagram showing the relationship between the amount of extension of the zoom lens barrel and the zoom rotation angle.

FIG. 15 is an explanatory diagram showing a relationship between a zoom rotation angle and a zoom position signal.

FIG. 16 is a schematic configuration diagram of a control system of a camera according to a second embodiment.

FIG. 17 is a flowchart showing a zoom position determination processing routine;

[Explanation of symbols]

 M1 Zoom drive unit M2 Zoom position detection unit M3 Interrupt detection unit M4 Control unit M5 Noise removal unit 31a Interrupt detection unit 36 Zoom position detection unit 51 Interrupt setting unit 52 Noise removal unit 53 Interrupt determination unit

Claims (3)

[Claims] 1. A zoom driving means for driving a zoom lens, a zoom position detecting means for detecting an absolute position signal of the zoom lens in conjunction with the driving of the zoom lens, and a zoom position detecting means. A camera zoom apparatus comprising: interrupt detection means for detecting a zoom position detection signal by interrupt processing; and determination means for determining that the zoom lens has been moved by an external force based on detection of the interrupt detection means. 2. The apparatus according to claim 1, wherein said interrupt detecting means includes a noise removing means.
A zoom device for the camera according to the above. 3. The camera zoom apparatus according to claim 1, wherein the zoom lens is returned to a predetermined position when the determination means determines that the zoom lens has been moved by an external force.