JP2003207842A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera that can obtain a signal output necessary for a duty drive by a space-saving pattern shape, and also prevent an erroneous signal due to chattering, etc. <P>SOLUTION: The camera is provided with a motor incorporated in the camera main body, a mirror driving cam driven by the rotation of the motor, a driving member for driving the mirror upward or downward cooperatively with the mirror driving cam, a phase detecting means for detecting the rotational phase of the mirror driving cam while rotating cooperatively with the mirror driving cam, a speed detecting means for detecting the driving speed of the mirror driving cam based on the detection output in a specified section of the phase detecting means, and a controller for performing the duty drive control of the motor based on the detection output of the speed detecting means, and it is characterized in that the controller is constituted so as to determine the duty drive cycle of one of the mirror-up drive section and the mirror-down drive section based on the driving speed of the mirror driving cam detected in the other section. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects a mirror up / down state and a shutter charge state by means of a camera control device, particularly a contact type encoder or the like, and controls each operation based on the information. Control device for a camera.

[0002]

2. Description of the Related Art Conventionally, a phase contact piece is attached to a cam for driving the mirror drive or shutter charge of a single-lens reflex camera and driving the mirror charge or shutter charge by operating the drive force of a motor that rotates in one direction. Has proposed a camera control device that detects the rotational phase of the cam by moving on the control pattern together with the cam, and controls the mirror drive and shutter charge.

FIG. 7A shows an example of the control pattern.
In the control pattern 410, patterns 412 and 413 are formed concentrically around a point 411. The pattern 412 is connected to GND. The patterns 412 and 413 are separated by two boundaries 414 and 415. The pattern 420 shown in FIG. 7B is a phase contact piece, and is in contact with the control pattern 410 at two contact points 421 and 422. The phase contact piece 420 rotates clockwise around the point 411 in association with the mirror up / down operation. The contact point 421 always slides on the pattern 412, and the contact point 422 moves in the pattern 412 by one rotation.
Pattern 413 to pattern 413 again
Slide back to.

FIG. 7 (c) shows the signal output SW1 according to the above-described pattern 410. High is pattern 413
Indicates that the pattern 412 is in contact with the pattern 412, and Low indicates that the pattern 413 is not in contact with the pattern 412.

The rotary sliding state shown in FIG. 7B shows the mirror-down position, which corresponds to the area 431 in FIG. 7C. The contacts 421 and 422 are both patterned 41
2 and the signal output SW1 extracted from the pattern 413 becomes High. The mirror-up operation is performed by rotating it clockwise from here. Contact 42
2 passes through the boundary 414, the signal output SW1 becomes High.
Switching from h to Low, the mirror-up operation stop control is performed, and the mirror-up operation is stopped. After the exposure operation, the mirror down operation is started, the phase contact piece 420 further rotates in the clockwise direction, and when the contact 422 passes the boundary 415, the signal output SW1 switches from Low to High, and the mirror down operation stop control is performed. , Stop in the mirror down state.

In the above-mentioned first conventional example, the stop of the mirror-up and mirror-down operations is realized by the reverse energization derailleur and the short brake for the drive motor after the switching of the signal output SW1 is detected. However, in the reverse energization brake from full energization of the motor, an excessive current flows, which adversely affects other operations (autofocus control, image stabilization control, etc.) performed in parallel.

In order to solve this problem, the reverse energization brake may be controlled from the state in which the motor is duty-driven to reduce the effective voltage. However, when the duty-driving is performed from the mirror-up start, the mirror-up time is increased. Becomes longer and the release time lag is extended. Therefore, it is desirable that the operation is such that full drive is performed at the start of mirror up, duty drive is switched during the operation, and then stopped by the reverse energization brake and short flakes. In this case, in order to determine the duty ratio that is suitable for the drive speed, set the control section so that the monitor section that measures the operation time and the signal output that determines the duty drive start point can be obtained during the mirror up / down operation. There is a need to.

FIG. 8 shows an example of a control pattern for dealing with the above problem as a second conventional example. The control pattern 510 is
Concentric patterns 512, 51 centered on the point 511
3 and 514 are provided. The pattern 512 is connected to GND. The pattern 513 has two boundaries 515 and 516 with the pattern 512,
Two boundaries 518 and 519 with the pattern 514
have. The pattern 514 also has two boundaries 517 and 520 with the pattern 512.

The pattern 530 is a phase contact piece, and the control pattern 51 has three contacts 531, 532, and 533.
It is in contact with 0. The phase contact piece 530 rotates clockwise around the point 511 in association with the mirror up / down operation. The contact 531 always slides on the pattern 512, and the contact 532 slides so as to switch from the pattern 512 to the pattern 514 by one rotation operation and return to the pattern 512 again. The contact 533 is a one-turn operation, and the pattern 51
2, 513, 512, 514, 513, and 514 are sequentially switched, and the slide is returned to the pattern 512 again.

FIG. 8C shows the signal output of the switches SW1 and SW2 by the control pattern 510. Figure 8
The bear in (b) indicates the mirror-down position and is in the state of the area 541. Contacts 531, 532, and 53
3 are both on the pattern 512, and the pattern 5
Signal output SW1 extracted from 14 and pattern 51
The signal outputs SW2 derived from 3 are both High. The mirror-up operation is performed by rotating it clockwise from here. First, the contact 533 passes the boundary 515, the signal output SW2 switches from High to Low, and then the boundary 516 passes and the signal output SW2 goes to L.
Switch from ow to High.

Next, the contact point 532 passes through the boundary 517 and is switched from the signal output SW1 or High to Low, and the mirror-up operation stop control is performed to stop in the mirror-up state. After the exposure operation, the mirror down operation is started, the phase contact piece 530 further rotates in the clockwise direction, the contact 533 first passes through the boundary 518, the signal output SW2 switches from Low to High, and then the boundary 519.
And the signal output SW2 switches from High to Low. Next, when the contact 533 passes through the boundary 520, the signal output SW1 switches from Low to High, the mirror-down operation stop control is performed, and the mirror-down operation is stopped.

Compared with the configuration of the first conventional example, one control pattern is added to the outside in order to provide a monitor section during mirror up / down. An example of the duty driving method with this signal output will be shown.

In the mirror-up operation, the motor of the drive source is fully driven to start up, and the time from the fall to the rise of the signal output SW2 is measured to detect the drive speed of the mirror-up operation. Based on this, the duty ratio is determined. Next, switching to duty driving is performed at the duty ratio previously determined from the rising timing of the signal output SW2. And the signal output S
At the falling timing of W1, the motor stop control is performed by the reverse energizing brake and the short brake, and the motor is stopped in the mirror-up state.

In the mirror-down operation, the motor of the drive source is started up by full drive, and the time from the fall to the rise of the signal output SW2 is measured to detect the drive speed of the mirror-down operation. The duty ratio is determined based on. Next, switching to duty driving is performed at the duty ratio previously determined from the rising timing of the signal output SW2. And the signal output S
The motor stop control is performed by the reverse energizing brake and the short brake at the falling timing of W1, and the motor is stopped in the mirror down state.

According to the driving method described above, control can be performed with a duty ratio according to the driving speed, and reverse energization braking from full driving can be avoided, so that an excessive current can be prevented from flowing.

[0016]

However, as shown in FIG.
In contrast to the control pattern shown in FIG. 8A, two concentric patterns are arranged in the radial direction.
The control pattern shown in (a) has a shape in which two concentric circular patterns are arranged in the radial direction, and has a drawback that the occupied area is widened. Further, since the drive speed is detected for each of the mirror up and the mirror down, there is room for improvement in that an erroneous signal may be detected by chattering or the like. .

The present invention has been made in view of the above problems, and an object thereof is to obtain a signal output required for duty driving with a space-saving pattern shape and prevent an erroneous signal due to chattering or the like. .

[0018]

In order to achieve this object, a camera according to a first aspect of the present invention comprises a motor built in the camera body, a mirror driving cam driven by the rotation of the motor, and a mirror driving. Member for driving the mirror up or down in cooperation with the cam for driving, phase detecting means for detecting the rotational phase of the mirror driving cam by rotating in conjunction with the mirror driving cam, and a predetermined phase detecting means. Based on the detection output of the section, a speed detection means for detecting the drive speed of the mirror driving cam, and a control device for performing the duty drive control of the motor based on the detection output of the speed detection means, the control device, The duty driving cycle of the other mirror is determined based on the driving speed of the mirror driving cam detected in the predetermined section of either mirror up or mirror down. Characterized in that it.

According to a second aspect of the present invention, there is provided a camera according to the first aspect.
The controller is characterized in that it determines the duty driving cycle when the mirror is driven down based on the drive speed of the mirror driving cam detected in the predetermined section during the mirror driving up.

The camera according to the invention of claim 3 is the camera according to claim 1.
Alternatively, in a second aspect of the present invention, the control device controls the other of the up-driving and down-driving of the mirror based on the driving speed of either one of up-driving and down-driving of the mirror and the set shutter speed. It is characterized in that the duty driving cycle is determined.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of a camera according to the present invention.

In FIG. 1, the mirror box 110 is
Main mirror 120, focal plane shutter 13
Store 0 etc. The hole 111 forms the center of rotation of the main mirror 120. The shaft 112 forms a rotation center of various levers. The boss 113 is used to hook the hook of the tension coil spring.

The main mirror 120 is installed in the mirror box 110 so as to be rotatable around the hole 111 as a center of rotation. The boss 121 receives an input from the mirror up lever during the mirror up operation, and receives an input from the mirror down spring during the mirror down operation. The focal plane shutter 130 is installed on the back surface of the mirror box 110. The mirror up lever 140 is installed on the mirror box 110 so as to be rotatable around a shaft 112. The input unit 141 receives an input from the drive source. The shutter charge output unit 142 engages with the shutter 130 to perform shutter charge. Mirror up output unit 143
Engages with the main mirror boss 121 to perform mirror up. The boss 144 is used to set the mirror down spring, and the spring hook 145 is used to hook the mirror up spring.

The diaphragm drive lever 150 is installed on the mirror box 110 so as to be rotatable around a shaft 112. The input unit 151 receives an input from the drive source. Spring loaded 152
Is used to hang the spring hook, spring hook 15
3 is used to hook the aperture driving spring. The diaphragm lever 160 is rotatably mounted on the mirror box 110 about a shaft 112, and engages a lever (not shown) provided on the interchangeable lens to drive the diaphragm in the lens.
The spring hook 161 is used to hook the diaphragm drive spring hook. The aperture return spring 170 is used for the mirror box 11
It is hung between 0 and the aperture drive lever 140, and when the mirror is down, the spring drive rotates the aperture drive lever counterclockwise to return the aperture lever to the initial position.

The mirror-up spring 180 is hung between the mirror box 110 and the mirror-up lever 140, and when the mirror is up, the spring-up force drives the mirror-up lever to rotate counterclockwise to raise the main mirror 120. The diaphragm drive spring 190 is hooked between the diaphragm drive lever 150 and the diaphragm lever 160, and rotates the diaphragm drive lever counterclockwise in conjunction with the operation of the diaphragm drive delay when the mirror is raised to perform a diaphragm operation.
The mirror down spring 200 has a mirror up lever 140.
The main mirror 120 is always urged in the down direction.

The control board 210 is a mirror box 110.
Is installed on the side of. The shaft 211 forms the center of rotation of the swing lever 220. The shaft 212 forms the center of rotation of the cam gear. The swing lever 220 is installed on the control board 210 so as to swing around a shaft 211 as a rotation center. The hole 221 forms the center of rotation of the swing lever 220. The output unit 222 is the input unit 14 of the mirror up lever 140.
1 to drive the mirror up lever 140. The output section 223 engages with the input section 151 of the diaphragm drive lever 150 and drives the diaphragm drive lever 150.

The cam follower 230 is the swing lever 22.
It is rotatably installed on the axis above 0. The cam gear 240 is
It receives a gear output from a drive gear train (not shown) having a motor as a drive source, rotates, and causes a swing lever 220 to swing by a cam. The hole 241 forms the center of rotation of the cam gear 240. Relatedly, the gear portion 242 and the cam 243
Is provided. A contact piece brush is installed on the surface of the cam gear 240 facing the control pattern plate. The control pattern plate 610 is fixed to the lid substrate 260. The lid substrate 260 is installed on the control substrate 210, and the swing lever 22
0 and the cam gear 240 are regulated in the thrust direction.

FIG. 2 shows a swing lever 220, a cam follower 230, and a cam gear 240 in a mirror-down bear.
Shows the relationship. The swing lever 220 is provided with cam follower shafts 224a and 244b, and the cam follower shaft 244 is provided with cam followers 230a and 2244.
30b is installed rotatably around the axis. Of these, the cam follower 230a is stopped while riding on the cam top portion of the cam 243.

FIG. 3 shows the relationship between the control pattern plate 610 and the contact piece brush 620 corresponding to the state of FIG. Details will be described with reference to FIG.

FIG. 4 shows the relationship between the swing lever 220, the cam follower 230, and the cam gear 240 in the mirror-up state. Cam follower 230b
However, it has stopped while riding on the cam top portion of the cam 243. FIG. 5 shows the relationship between the control pattern plate 610 and the contact piece brush 620 corresponding to the state of FIG. Details will be described with reference to FIG.

The shape of the control pattern 610 is shown in FIG. The control pattern 610 is provided with patterns 612, 613, and 614 concentrically around a point 611. The pattern 612 is connected to GND. The pattern 613 has two boundaries 61 with the pattern 612.
5 and 616. The pattern 614 also has two boundaries 617 and 618 with the pattern 612. The phase contact piece 620 has two contacts 621 and 622.
In contact with the control pattern 610. The phase contact piece 620 is a point 611 associated with the mirror up / down operation.
Rotate clockwise around. The contact point 621 always slides on the pattern 612, and the contact point 622 slides so as to switch to the patterns 612, 613, 612, and 614 in order by one rotation operation and return to the pattern 612 again.

FIG. 6C shows the signal outputs SW1 and SW2 of the control pattern 610. The state of FIG. 6 (b) is
The mirror down position is shown and corresponds to the area 631. The contacts 621, 622, and 623 are both on the pattern 612, and the signal output SW1 extracted from the pattern 614 and the signal output SW2 extracted from the pattern 613 are both High. The mirror-up operation is performed by rotating it clockwise from here.
First, the contact 622 passes through the boundary 615, and the signal output SW
2 switches from High to Low, then boundary 6
After passing through 16, the signal output SW2 is switched from Low to High. Next, the contact point 622 passes through the boundary 617, the signal output SW1 is switched from High to Low, the mirror-up operation stop control is performed, and the mirror-up operation is stopped. After the exposure operation, the mirror down operation is started,
The phase contact piece 620 further rotates clockwise, and the contact 622
Passes through the boundary 618 and the signal output SW1 changes from Low to H
It is switched to high, mirror down operation stop control is performed, and the mirror is stopped in the mirror down state.

Compared with the structure of the conventional example, one control pattern for providing a monitor section during mirror up is added, but it is not added outside but is added in a form that digs into the conventional pattern. Therefore, the size of the control pattern is the same as that of the conventional example shown in FIG. The monitor section is not provided during the mirror down. The duty driving method with this signal output will be described below.

In the mirror-up operation, the drive source motor is fully driven to start up, and the time from the fall to the rise of the signal output SW2 is measured to detect the drive speed of the mirror-up operation. The duty ratio is determined based on. Next, switching to duty driving is performed at the duty ratio previously determined from the rising timing of the signal output SW2. And the signal output S
At the falling timing of W1, the motor stop control is performed by the reverse energizing brake and the short brake, and the motor is stopped in the mirror-up state.

In the mirror-down operation, the motor of the drive source is started up in full drive, and after a predetermined time has passed, the drive is switched to duty drive at the duty ratio determined in mirror up. Then, the motor stop control by the reverse energization brake and the short brake is performed at the falling timing of the signal output SW1 to stop in the mirror down state. As the duty ratio when the mirror is down, the duty ratio when the mirror is up may be used as it is, or may be used by converting it into a duty ratio multiplied by a predetermined coefficient.

In the exposure operation after the mirror-up operation, when the valve or shutter magnet is energized for a long time, it is considered that the drive voltage when the mirror is down is lowered. The driving speed may be too slow when driving with. As a countermeasure, in the case of a valve or a long shutter speed, a coefficient larger than 1 is easily prepared for the duty ratio determined when the mirror is raised, and the duty ratio is converted by using this coefficient, or a full duty cycle is used. It is effective to drive.

Although the present invention has been described with reference to the embodiments, various modifications can be made according to the technical idea of the present invention. For example, in the above-described embodiment, the duty ratio is determined only when the mirror is up, and the duty ratio when the mirror is up is directly used for the mirror down operation. However, conversely, the duty ratio is only when the mirror is down. The ratio may be determined and the duty ratio when the mirror is down may be used as it is for the mirror-up operation.

[0039]

As described above, according to the camera of the present invention, the duty driving cycle of the other is determined based on the driving speed of the mirror detected in the predetermined section of either the mirror up or the mirror down. As a result, it is not necessary to provide a monitor section for driving speed detection in the mirror-down area (or the mirror-up area), and the control pattern area can be kept small.

Further, since the mirror driving speed is detected only in the predetermined section of either the mirror up or the mirror down, it is compared with the case where the mirror driving speed is detected in both the mirror up and the mirror down. Then, it becomes possible to more effectively prevent an erroneous signal due to chattering or the like.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a camera according to the present invention.

FIG. 2 is a front view showing an embodiment of a camera according to the present invention.

FIG. 3 is a front view showing an embodiment of a camera according to the present invention.

FIG. 4 is a front view showing an embodiment of a camera according to the present invention.

FIG. 5 is a front view showing an embodiment of a camera according to the present invention.

FIG. 6 is a front view and a waveform diagram showing an embodiment of a camera according to the present invention.

FIG. 7 is a front view and a waveform diagram showing an example of a conventional camera.

FIG. 8 is a front view and a waveform diagram showing an example of a conventional camera.

[Explanation of symbols]

110 mirror box 111 holes 112 axes 113 Boss 120 main mirror 121 Main Mirror Boss 130 focal plane shutter 140 Mirror up lever (drive lever) 141 Input section 142 Shutter charge output section 143 Mirror up output section 144 Boss 145 spring loaded 150 Aperture drive lever 151 Input section 153 spring 160 lever 170 spring 180 mirror up spring 190 Drive spring 200 Mirror down spring 210 control board 211 axis 212 axes 220 Swing lever 221 holes 222 Output section 223 Output section 224a Cam follower shaft 230 cam followers 230a Cam follower 230b Cam follower 240 cam gear 241 holes 242 gear 243 cam 244 Cam follower axis 260 lid substrate 610 control pattern 611 points 612 patterns 613 pattern 614 pattern 615 border 616 border 617 border 618 border 620 Phase contact piece 621 contact 622 contacts 631 area

Claims (3)

[Claims] 1. A motor built into a camera body, a mirror driving cam driven by rotation of the motor, and a driving member which is linked to the mirror driving cam and drives the mirror up or down. Phase detection means that rotates in conjunction with the mirror drive cam to detect the rotational phase of the mirror drive cam, and drive of the mirror drive cam based on the detection output of the phase detection means in a predetermined section A speed detection means for detecting a speed, and a control device for performing duty drive control of the motor based on a detection output of the speed detection means, wherein the control device is one of mirror up and mirror down. A camera characterized in that the other duty drive cycle is determined based on the drive speed of the mirror drive cam detected in a predetermined section. 2. The control device determines a duty driving cycle during down driving of the mirror based on a driving speed of the mirror driving cam detected in the predetermined section during up driving of the mirror. The camera according to claim 1, wherein the camera is a camera. 3. The control device controls the up-driving and down-driving of the mirror based on either one of the driving speed during up-driving and down-driving of the mirror and the set shutter speed. 3. The other duty driving cycle is determined.
The camera described in.