JP2001045793A - Drive state-detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce measurement time for improving productivity by detecting the loaded state of a drive source when driving a device to be driven with the drive source. SOLUTION: Although a motor 17 for driving the mirror frame of the drive state-detecting device is driven by a motor IC14 and a bridge circuit, the rotation of the mirror frame drive motor 17 is controlled since the voltage of transistors Tr1, Tr2, Tr3, and Tr4 is controlled according to a logic table using a motor IC24. Also, an ammeter 22 is connected to the output line of an external power supply 21, an output current I1 of the external power supply is composed by the sum of a current I2 being supplied to a CPU 23, a current I3 being supplied to the motor IC24, and a current I4 flowing to a bridge circuit. Then, by driving a drive source and at the same time monitoring output from the drive state-detecting device, the mirror frame drive motor 17 is adjusted. As a result, an adjustment member can be adjusted while being driven, measurement time can be reduced and productivity can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving state detecting device, and more particularly, to a driving state Shii depopulated area for detecting a load state of a driving section and monitoring a coupling state between the driving section and a driven section. It is.

[0002]

2. Description of the Related Art In a power transmission mechanism that drives a mechanism member as a driven member by a motor, it has been conventionally known to provide an adjusting member for adjusting a loss such as play or friction.

For example, in Japanese Patent Application Laid-Open No. Hei 8-110460, a lens frame having a structure in which a lens frame is supported by a support portion fitted to a guide shaft so as to be able to move straight forward and forward and backward by a rack meshing with a feed screw. An apparatus is disclosed. In this conventional lens driving device, in order to remove the looseness of the engagement between the feed screw and the rack and the looseness of the fitting at the supporting portion, the loosening of the rack is performed by sandwiching the spring with the spring member. A moment is applied to the supporting portion to remove play at the supporting portion.

[0004]

In such a conventional lens driving device, the adjusting operation of the adjusting member is performed in a static state with the motor stopped.

That is, when adjusting the lens driving device,
For example, the adjustment is performed while measuring the moving force of the moving member with a measuring tool or the like.

However, in the power transmission mechanism with such an adjustment, an intended adjustment result cannot be obtained in many cases due to a difference in a friction condition or the like during driving.

Further, for example, the force of the moving member or the spring described above has to be measured each time the moving member is moved, which is troublesome. In particular, when fine adjustment is performed, it is inconvenient to improve productivity.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and facilitates adjustment of an adjusting member using a simple device in a dynamic state, that is, a state in which a driven device is driven by a driving source. It is an object of the present invention to provide a driving state detection device that can perform the measurement, shorten the measurement time, and improve the productivity.

[0009]

That is, the present invention provides a driving source which is rotated by electric power, a driven device driven by the driving source, and the driving source for driving the driven device by the driving source. And a driving state detecting means for detecting the load state of the above.

The present invention further comprises a movable lens frame, a motor for driving the lens frame, and driving state detecting means for driving the lens frame by the motor and detecting a driving state thereof. It is characterized by.

In the driving state detecting device according to the present invention,
The driving source is rotated by the electric power, and the driven device is driven by the driving source. Then, in the drive state detecting device, the load state of the drive source when the driven device is driven by the drive source is detected.

In the driving state detecting device according to the present invention, the movable lens frame is driven by a motor. Then, the lens frame is driven by the motor, and the driving state is detected by the driving state detecting means.

Accordingly, the drive state detecting device is a drive source in a dynamic state, that is, a state in which the driven device is driven by the drive source, in the power transmission mechanism that drives the mechanism member as the driven member by the motor. Since the adjustment operation of the adjustment member is performed while monitoring the operation state of, a desired adjustment state can be easily obtained.

[0014]

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

FIG. 2 shows an embodiment of the driving state detecting device according to the present invention. FIG. 2 is a longitudinal sectional view taken along the optical axis of the lens frame device. FIG. 3 is a front view of the lens frame device. 4 is an enlarged view showing a fitting state of a notch portion of the first lens frame and a sliding shaft portion constituting the movable lens frame portion of the lens frame device, and FIG. 5 is a movable lens frame portion incorporated in the lens frame device. It is a perspective view of.

The lens frame device is mainly composed of a fixed frame 1, a cam ring 2 fitted into the outer peripheral portion of the fixed frame 1 and rotatably supported, and a movable lens frame portion driven forward and backward by the cam ring 2. And 3. The movable lens frame 3 holds the first lens group 4, and is supported by the second lens frame 7 so as to be movable forward and backward in the optical axis O direction. And a second lens frame 7 supported by the fixed frame 1 so as to be able to advance and retreat in the direction of the optical axis O, and a first lens frame 5 fixed to the second lens frame 4 and slidable in the direction of the optical axis O. Guide shaft 8 and guide shaft 9 as linear support members for guiding
It is composed of

The fixed frame 1 has three linear guide grooves 1
a, a straight escape groove 1b, and an adjustment through hole 1c.

The cam ring 2 has a gear portion 2a on the outer peripheral portion thereof, three oblique cam grooves 2b for driving the second lens frame 7 forward and backward, and a driving device for driving the first lens frame 5 forward and backward. Is provided with one oblique cam groove 2c and an adjustment through hole 2d.

Further, a drive gear 15 driven through a gear train by a pinion 16 of a lens frame drive motor (M) 17 which will be described in detail later meshes with a gear portion 2a on the outer periphery of the cam ring 2. . The amount of rotation of the drive motor 17 can be detected by an output pulse of a photo interrupter (PI) 19 obtained through a slit plate 18 fixed to a motor shaft.

The second lens frame 7 has three cam followers 11 fitted in the cam groove 2b of the cam ring 2 on the outer peripheral portion thereof.
And shaft support holes 7a and 7b, which are two shaft support holes disposed symmetrically with respect to the optical axis O, and an adjustment screw hole 7c disposed on a side surface of the shaft support hole 7b. I have. The shaft support hole 7a is a support hole having a loose fit with respect to the guide shaft 8, and the shaft support hole 7b is precisely fitted with the support shaft portion 9b of the guide shaft 9 (fitting with a very small gap). ). The adjusting screw hole 7c is provided as one of the adjusting means.
A screw hole into which a set screw is screwed.

The first lens frame 5 has one cam follower 12, a shaft hole 5a provided at a position facing the shaft support holes 7a and 7b of the second lens frame 7, and a U-shaped guide portion. And a notch 5b. The cam follower 12 is a cam follower that penetrates through the clearance groove 1b of the fixed frame 1 with play and is slidably fitted into the cam groove 2c of the cam ring 2.

The shaft hole 5a is a shaft hole in which the guide shaft 8 is slidable in a precision fitting state, and the notch portion 5b is a notch slidable in the sliding shaft portion 9a of the guide shaft 9. Department.

The guide shaft 9 has a sliding shaft portion 9a fitted into the notch portion 5b of the first lens frame 5, and a second lens frame 7
And a support shaft portion 9b fitted into the shaft support hole 7b. A slide 9c for tool adjustment is provided at the tip of the slide shaft portion 9a.

As shown in FIG. 4, the sliding shaft portion 9a has an elliptical cross section having a non-circular cross section. When the guide shaft 9 is rotated around the support shaft 9b, the width of the sliding shaft 9a in the X direction orthogonal to the optical axis O (see FIG. 4) changes symmetrically with respect to the axis. The change range of the width dimension is a range that covers the width of the cutout portion 5b of the first lens frame 5. The support shaft 9b has a circular cross-section coaxial with the axis of the slide shaft 9a. The cross section of the sliding shaft portion 9a may be an elliptical cross section or the like in addition to the elliptical cross section.

FIG. 1 is an electric circuit diagram for assembling and adjusting a lens frame advance / retreat drive unit of a camera incorporating the lens frame device in the first embodiment.

The electric circuit includes an external power supply 21 and an ammeter 22 connected to the external power supply 21 for measuring a lens frame driving current.
, A CPU 23 connected to the series circuit to control the entire camera, a motor IC 24 for motor drive controlled by the CPU 23, and a transistor Tr1 for driving the lens frame drive motor 17.
To Tr4.

The lens frame drive motor 17 includes a motor IC 2
4 and a motor for driving the lens frame forward and backward driven by the bridge circuit. The rotation of the lens frame drive motor 17 is controlled by controlling the voltage of the transistors Tr1, Tr2, Tr3 and Tr4 by the motor IC 24 according to the logic table shown in FIG. Here, D1, D2, D3, and D4 are control terminals for supplying pulse signals to the control terminals of the transistors Tr1, Tr2, Tr3, and Tr4, respectively.

The ammeter 22 is connected to the output line of the external power supply 21 and monitors the output current I ₁ of the external power supply to determine the state of the load. The output current I _1, as shown in FIG. 1, formed by the sum of the current I ₄ flowing through the current I ₃ and the bridge circuit is supplied to the current I ₂ and the motor IC24 supplied to the CPU 23.

FIG. 7 is a characteristic diagram showing the relationship between the output current I1 and the rotation angle of the sliding shaft 9a according to the _first embodiment.

In this characteristic diagram, the slit 9c for tool adjustment is rotated by an unillustrated adjustment tool or the like.
The sliding shaft 9a is rotated in a predetermined direction from a no-load state.
Then, up to the rotation angle θ ₁ , I ₁ = I ₂ + I ₃ + I _4. However, when the sliding shaft 9 a is rotated to exceed the rotation angle θ ₁ , the amount of output current increases. This is because a load is applied when the sliding shaft portion 9a comes into contact with the notch portion 9b.

Therefore, in order to obtain a state in which the gap X between the sliding shaft portion 9a and the notch portion 5b is almost zero in order to eliminate the play of the lens barrel device, a slight current is applied from the no-load state. In the state where it has begun to increase, that is, θ ₁ to θ _{2 in} FIG.
Should be adjusted to the range.

For example, if the target of adjustment by the sliding shaft portion 9a is a rotation angle θ _{1 to} θ ₂ , the allowable current increase is Δ
I. Therefore, the ammeter 22 is monitored, and if the increasing current ΔI is detected, the adjustment may be terminated.

As described above, by adjusting the sliding shaft portion by monitoring the ammeter, adjustment of the lens frame device can be easily performed.

Next, a second embodiment of the present invention will be described.

In the above-described first embodiment, the output current monitored by the ammeter monitors not only the current consumption of the lens frame drive motor 17 but also the current consumed by the CPU 23 and the motor IC 24. In the second embodiment, the output flowing through the CPU 23 and the motor IC 24 is not monitored, and the current flowing only through the lens frame drive motor 17 is detected to increase the resolution.

FIG. 8 is an electric circuit diagram for assembling and adjusting a lens frame advance / retreat drive unit of a camera in which the lens frame device is incorporated in the second embodiment.

In FIG. 8, a resistor R1 is connected to a bridge circuit composed of a lens frame drive motor 17 and transistors Tr1 to Tr4 as shown. One end of the resistor R1 is connected to the non-inverting input terminal of the operational amplifier 26, and the other end is connected to the inverting input terminal of the operational amplifier 26 via the resistor R2. A resistor R3 and a capacitor C1 are connected between the output terminal of the operational amplifier 26 and the inverting input terminal.
Are connected.

In such a configuration, the current consumed by the lens frame drive motor 17 is converted into a minute voltage by the resistor R 1, and is amplified non-inverted by the operational amplifier 26. The output voltage Vout of the operational amplifier 26 becomes _{Vout = R1 × I 5 × (} (R2 + R3) / R2).

The output voltage Vout may be A / D converted by the CPU 23 to determine whether the output voltage Vout falls within a desired value range, or may be monitored by a voltmeter.
The capacitor C1 forms a low-pass filter and removes brush noise of the lens frame drive motor 17.

FIG. 9 is a characteristic diagram showing the relationship between the output voltage and the rotation angle of the sliding shaft 9a according to the second embodiment.

In this characteristic diagram, the slit 9c for tool adjustment is rotated by an adjustment tool (not shown) or the like.
The sliding shaft 9a is rotated in a predetermined direction from a no-load state.
Then, for example, if the target of adjustment by the sliding shaft portion 9a is the rotation angle θ _{1 to} θ ₂ , the allowable voltage increase is ΔV. Therefore, by monitoring the output of the operational amplifier 26,
If the increasing voltage ΔV is detected, the adjustment may be terminated.

Next, the operation of the second embodiment of the present invention will be described with reference to FIGS.

FIG. 10 is a characteristic diagram showing the output waveform of the lens frame drive motor 17, and FIG. 11 is a flowchart for explaining the adjustment operation of the lens frame device according to the second embodiment.

[0044] First, at step S1, the lens frame drive motor 17 driven by the lens is abutted at one end of the optical axis direction (through T _1). In this case, since the motor 17 is in a state where a voltage is applied without rotating (Vstp), a high current consumption flows. Therefore, the value of the output Vout increases.

Next, at step S2, the lens frame drive mode is set.
Is rotated in a direction opposite to that of step S1.
The lens 17 is started to drive and the current consumption of the motor 17
Decreases (T₁~). Thereby, step S3
Entering the stabilization time (~ T _Two), Mirror in step S4
The output voltage Vout of the frame drive motor 17 becomes Vmin.

In this state (T _2- ), the rotation angle of the sliding shaft 9a is adjusted (coarsely adjusted). When the sliding shaft 9a comes into contact with the notch, the output voltage Vout starts to gradually increase.

Here, in step S5, it is determined whether or not the output voltage Vout has reached the voltage Vstp when the lens is applied. If the output voltage Vout has reached the voltage Vstp, the lens has been brought into contact with the opposite end. Therefore, the process proceeds to step S6, in which the lens frame driving motor 17
Is driven in the opposite direction. And step S
At 7, the operation is performed for a stable time as in step S3, and the adjustment operation is performed again. Then, step S
Go to 5.

On the other hand, if the output voltage Vout has not reached the voltage Vstp in step S5, the process proceeds to step S8, where the output voltage Vout is a voltage value that is the upper limit of the target adjustment range, ie, Voltage Vmi during settling time
It is determined whether or not a value obtained by adding a predetermined voltage ΔV2 to n has been reached.

Here, if the output voltage Vout exceeds the upper limit, the process proceeds to step S5. On the other hand, if the output voltage Vout has reached the upper limit value (T ₃ ), the process proceeds to step S9, where the output voltage Vou is again output.
It is determined whether or not t has reached the voltage Vstp (~
T _4).

At step S9, the output voltage V
It is determined whether out has reached the voltage Vstp.
If the output voltage Vout has reached the voltage Vstp, the lens is in contact with the opposite end, so that
Move to step S10. Then, in steps S10 and S11, after the same processing as in steps S6 and S7 described above is performed, the process proceeds to step S9.

On the other hand, in step S9, the output power
If the voltage Vout has not reached the voltage Vstp, the step
Proceeding to S12, the output voltage Vout is adjusted to the target value.
The voltage value at the upper end of the range, ie the voltage V during the settling time
It became smaller than the value obtained by adding the predetermined voltage ΔV2 to min.
Is determined (T_Four~ T_Five). This is _Two
~ T_ThreeThis is a fine adjustment period for the coarse adjustment.

Here, if the output voltage Vout is still higher than the upper limit, the process proceeds to step S9.
On the other hand, if the output voltage Vout is smaller than the upper limit value (T5 _to ), the process proceeds to step S13, where the output voltage Vout is a voltage value that is the lower limit of the target adjustment range,
That is, it is determined whether or not the value is greater than a value obtained by adding the predetermined voltage ΔV1 to the voltage Vmin during the stable time.

In step S13, when the output voltage Vout becomes lower than the voltage value which is the lower limit of the target adjustment range, it is determined that the lens has been returned too much, and the process proceeds to step S5, and the subsequent processing is repeated. . Also, the output voltage V
If out is higher than the voltage value that is the lower limit of the adjustment range, that is, Vmin + ΔV1 ≦ Vout ≦ Vmin + ΔV2, the desired adjustment range is obtained, and the adjustment is completed and this routine ends.

As described above, by adjusting the sliding shaft portion by monitoring the output voltage, adjustment of the lens barrel device can be easily performed.

Further, according to the second embodiment, the desired adjustment range can be obtained at a large ratio with respect to the entire voltage output, so that the adjustment can be further performed as compared with the above-described first embodiment. It will be easier.

Next, a third embodiment of the present invention will be described.

FIG. 12 is an electric circuit diagram for assembling and adjusting a lens frame advance / retreat drive unit of a camera in which the lens frame device is incorporated in the third embodiment.

In FIG. 12, a CPU 2 for driving a motor is provided.
Reference numeral 3 denotes a waveform shaping circuit composed of resistors R11, R12, R13 and a transistor Tr5, and the brightness of a slit plate 18 fixed to a motor shaft of a lens frame drive motor (not shown) via a resistor R14. A photo interrupter 19 for detecting rotation is connected.

In such a configuration, the rotational speed of the motor is detected by the photo interrupter 19 from the slit plate 18 fixed to the motor shaft of the lens frame drive motor. Then, when the signal of the photo interrupter 19 is shaped by the waveform shaping circuit, the signal is taken into the CPU 23, whereby the pulse width is measured.

FIG. 13 is a diagram showing the output waveform of the photointerrupter in the third embodiment.

As for the output of the photo interrupter 19, the ratio of the measurement of t ₁ and t ₂ varies depending on the circuit and the current variation. Therefore, the measurement is performed for at least one cycle of the pulse. In FIG. 13, four periods of time T ₁₁ , T ₁₂ ,
It is to be compared for T _13.

When the load is light (no load state), the rotation speed of the motor increases, and the time T11 decreases. Then, as the load increases (the contact between the sliding shaft portion and the notch increases), the cycle becomes longer as in the time periods T12 and T13.

Therefore, similarly to the above-described first and second embodiments, the desired adjustment range is set to, for example, T11 to T11.
As 12, the CPU 23 may determine this range and output the result.

According to the above embodiment of the present invention,
The following configuration can be obtained.

(1) A driven means, a driving source for driving the driven means, and a driving state detecting means for driving the driven source by the driving source and detecting a driving state thereof. A driven means adjusting device for monitoring an output from the drive state detecting means while driving the drive source and adjusting the driven means.

(2) The driven means adjusting device according to (1), wherein the driving state detecting means detects a current consumption or a rotation state of the driving source.

(3) A movable lens frame, a motor for driving the lens frame, and driving state detecting means for driving the lens frame by the motor and detecting a driving state of the lens frame. A lens frame adjusting device for monitoring an output from the drive state detecting means while driving the lens unit and adjusting the lens frame.

(4) A driving source for converting electric power into rotational force, driving state detecting means for detecting electric power or rotational speed of the driving source, and a coupling state between the driving source and the driving source are adjustable. And a driven device driven by a source, wherein the coupling state of the driven device is adjusted based on an output of the driving state detecting means.

(5) The driving mechanism according to (4), wherein the driven device is a camera frame device.

(6) The driving source is a motor, and the driving state detecting means detects a current or a rotation speed of the motor. (4) or (5).
4. The driving mechanism according to 1.

[0071]

As described above, according to the present invention, the adjusting operation of the adjusting member can be easily performed using a simple device in a dynamic state, that is, in a state where the driven device is driven by the driving source. It is an object of the present invention to provide a driving state detecting device capable of shortening the measuring time and improving the productivity.

[Brief description of the drawings]

FIG. 1 is an electric circuit diagram for assembling and adjusting a lens frame advance / retreat drive unit of a camera in which the lens frame device is incorporated according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing an embodiment of a drive state detecting device according to the present invention, which is taken along an optical axis of a lens barrel device.

FIG. 3 is a front view of the lens barrel device of FIG. 2;

FIG. 4 is an enlarged view showing a fitting state of a notch portion of a first lens frame and a sliding shaft portion constituting a movable lens frame portion of the lens frame device of FIG. 2;

FIG. 5 is a perspective view of a movable lens frame unit incorporated in the lens frame device of FIG. 2;

FIG. 6 is a diagram showing a logic table of voltages controlled by the motor IC 24.

FIG. 7 is a characteristic diagram showing a relationship between the output current I1 and the rotation angle of the sliding shaft 9a according to the _first embodiment.

FIG. 8 is an electric circuit diagram for assembling and adjusting a lens frame advance / retreat drive unit of a camera in which the lens frame device is incorporated in the second embodiment.

FIG. 9 shows the output voltage and the sliding shaft 9 according to the second embodiment.
It is a characteristic view showing the relationship with the rotation angle of a.

FIG. 10 is a characteristic diagram showing an output waveform of a lens frame drive motor 17;

FIG. 11 is a flowchart illustrating an adjustment operation of the lens barrel device according to the second embodiment.

FIG. 12 is an electric circuit diagram for assembling and adjusting a lens frame advance / retreat drive unit of a camera in which a lens frame device is incorporated according to a third embodiment.

FIG. 13 is a diagram illustrating an output waveform of a photo interrupter according to a third embodiment.

[Explanation of symbols]

 Reference Signs List 1 fixed frame, 2 cam ring, 3 movable lens frame, 4 first group lens, 5 first lens frame, 5a shaft hole, 5b notch, 6 second group lens, 7 second lens frame, 8, 9 Guide shaft, 9a sliding shaft, 9b support shaft, 9c slot, 12 cam follower, 15 drive gear, 16 pinion, 17 lens frame drive motor (M), 18 slit plate, 19 photo interrupter (PI), 21 external Power supply, 22 ammeter, 23 CPU, 24 motor IC.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H044 DB02 DC10 DD03 DE02 5H571 AA20 CC01 HA01 HA08 HA18 JJ02 JJ03 JJ16 JJ18 JJ26 LL01 LL22 LL23

Claims (3)

[Claims] 1. A driving source that is rotated by electric power, a driven device driven by the driving source, and a driving state detection that detects a load state of the driving source when the driven device is driven by the driving source. And a driving state detecting device. 2. The driving state detecting device according to claim 1, wherein the driving state detecting means detects a current consumption or a rotation speed of the driving source. 3. A movable lens frame, a motor for driving the lens frame, and driving state detecting means for driving the lens frame by the motor and detecting a driving state of the lens frame. Drive state detecting device.