JPH0253009A - Machine motion detector - Google Patents

Abstract

PURPOSE:To decrease the number of components and to prevent the device from increasing in size, weight, and cost by providing an optical detecting means which detects the motion of a 1st motion member and a 2nd motion member which is so arranged that its holes can be detected together with holes of the 1st motion member. CONSTITUTION:A distance ring 7 (2nd motion member) is provided at an axially adjacent part on the same optical axis 5 with a driving ring (1st motion member) and this distance ring 7 is rotated around the optical axis 5 to drive a lens part in the axial direction of the optical axis 5. Then when the lens part is put focusing operation, the driving ring 6 and distance ring 7 are driven integrally and the light projected on the photodetection part 21b of a photocoupler 21 (detecting means) from the projection part 21a passes only holes at the part where holes 7f and 6f are superposed one over the other, thereby outputting a detection pulse. Consequently, the number of the components of the detector is decreased and the device is prevented from increasing in size, weight, and cost.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a mechanical motion detection device, and more particularly to a mechanical motion detection device capable of detecting the relative motion relationship of a plurality of moving members using the same detection means. be.

[Conventional technology]

Conventional mechanical motion detection devices include, for example, detecting the position of a moving member by sliding a brush contact piece on a pattern formed on the surface of the moving member, or detecting the position of a moving member by detecting a slit formed in the moving member. There has been a system that detects the position of a moving member by detecting it with an optical detection means such as a photocoupler.

[Problem to be solved by the invention]

However, in the conventional mechanical movement detection device described above, one brush contact piece is used to detect the position of one moving member.
Alternatively, since one optical detection means is used in a one-to-one relationship, the same number of detection means is required to detect the positions of multiple moving members, which increases the number of parts of the detection device and increases the number of parts in the detection device. This has led to problems such as increased size, weight, and cost.

Furthermore, since it is completely impossible to simultaneously detect the integral motion of multiple moving members or to detect their relative motion separately using the same detection means, the above-mentioned method is also impossible. It was causing problems.

[Means to solve the problem]

Therefore, in order to solve the above-mentioned problems, the mechanical motion detection device according to the present invention includes a first moving member having a plurality of holes opened at a predetermined pitch, and a first moving member that optically detects the plurality of holes of the first moving member. an optical detection means for detecting the movement of one moving member; and a plurality of holes opened at a pitch that is an integral multiple of two or more of the plurality of holes of the first movement member;
This configuration includes a plurality of holes of the moving member and a second moving member arranged so as to be able to detect the plurality of holes.

[For production]

According to the above configuration, when the first moving member and the second moving member move integrally, the plurality of holes in the second moving member are detected by the optical detection means, and the second moving member stops and the first moving member moves. When only the members move, by detecting the plurality of holes in the first moving member with the same optical detection means, it is possible to simultaneously detect the integral movement of the plurality of moving members or to detect their relative movements. It becomes possible to perform separate detection using one detection means. Therefore, the number of parts of the detection device is reduced, and it is possible to prevent the device from increasing in size, weight, cost, etc.

〔Example〕

Embodiments of the present invention will be described below based on the drawings. 1 to 7 are diagrams showing an embodiment of a mechanical motion detection device according to the present invention.

FIG. 1 is a front view showing an automatic focus/exposure operating device of a camera in which the present invention is used. In the figure, 2 is a gear, and this gear 2 rotates together with a rotor shaft 1 of a step motor whose rotation is variably controlled in forward and reverse directions by a control circuit not shown. The gear 2 meshes with a large-diameter tooth portion 4a of an intermediate gear 4 that is pivotally supported on a shaft 3, and a small-diameter tooth portion 4a of the intermediate gear 4 engages with the gear 2.
A toothed portion 6a of a drive ring 6 (first moving member) is engaged with b.

Further, the drive ring 6 is rotationally driven in both forward and reverse directions around the optical axis 5 by a step motor. Shaft portions 5b and 5c are provided at two locations around the drive ring 6, and these shaft portions 5
Two elongated holes each having an abutting portion 6d at the end thereof are formed radially inward from b and 5c. Further, a cam portion 6e is formed on the right side of the drive ring 6 on the right side in the figure, and a plurality of holes 6f are formed at a predetermined pitch on the upper left side of the figure.

A distance ring 7 (second moving member) is provided axially adjacent to the drive ring 6 on the same optical axis 5, and by rotating around the optical axis 5, the distance ring 7 moves a lens portion (not shown). It can be driven in the axial direction of the optical axis 5. Pins 7a and 7b that protrude toward the drive ring 6 are formed on the back side of the distance ring 7 in the figure, and these pins 7a and 7b
are fitted into two elongated holes in which the contact portions 6d of the drive ring 6 are formed.

Further, the distance ring 7 has ratchet teeth 7e on its periphery.
Cam portion 7c formed at the end of this ratchet tooth 7e portion
and a switch actuating portion 7d, and a plurality of holes 7f are formed on the same pitch arc as the pitch arc of the plurality of holes 6f of the drive ring 6 and at a pitch twice the pitch of the holes 6f. It is formed. That is, in the drawings, circles indicated by solid lines indicate both holes 6f and 7f that overlap each other, and circles indicated by broken lines indicate only hole 6f.

A spring 8 is interposed between the cam portion 7C of the distance ring 7 and the drive ring 6, and this spring 8 rotates the distance ring 7 clockwise with respect to the drive ring 6, and rotates the distance ring 7 clockwise with respect to the drive ring 6. , 7b are urged to abut against abutting portions 6d at the ends of two elongated holes in the drive ring 6 for positioning.

On the back side of the drive ring 6 in the figure, there are two shaft parts 6b on its circumference.
, 6c, the end of the sector (blade) 9.10 is pivotally supported,
The optical axis 5 from the shaft portions 6b and 6c of these sectors 9 and 10
Operating holes 9a and 10a are formed on each side.

Since the pins 7a and 7b of the distance ring 7 are fitted into the operating holes 9a and 10a of these sectors 9.10, the sectors 9.10 are rotated by relative rotation between the distance ring 7 and the drive ring 6. It rotates to open and close the shirt opening 20.

A return detection switch 11 is provided near the lower left force of the drive ring 6 in the figure, and this return detection switch 11 is activated when the distance ring 7 rotates counterclockwise and then reverses and rotates clockwise to initialize. When the switch is returned to the position, the switch actuating portion 7d is contacted and turned off.

There is a ratchet pawl 13 near the upper right side of the distance ring 7 in the figure.
is provided rotatably supported by a shaft 12, and this ratchet pawl 13
When the is rotated counterclockwise, the claw 1 at the tip of the
3a engages with ratchet teeth 7e of distance ring 7. A square locking portion 13b is formed protruding from the rear side of the rear end of the ratchet pawl 13 in the figure, and a spring 14 is also provided at the rear end of the ratchet pawl 13 between it and the stationary portion. The ratchet pawl 13 is biased counterclockwise.

A pawl position detection switch 15 is provided near the rear end of the ratchet pawl 13, and when the ratchet pawl 13 rotates clockwise, the lower surface of its locking portion 13b comes into contact with the pawl position detection switch 15. It is turned OFF.

Similarly, a locking pawl 17 pivotally supported by a shaft 16 is provided near the rear end of the ratchet pawl 13, and when this locking pawl 17 rotates clockwise, a pawl portion 17a at the tip thereof engages with the ratchet pawl. It can be locked on the upper surface of the locking action part 13b of No. 13. The rear end of the locking pawl 17 has a pin portion 17b, and this pin portion 17b is connected to the cam portion 6e of the drive ring 6.
When pressed to rotate counterclockwise by
The pawl portion 17a separates from the upper surface of the locking portion 13b of the ratchet pawl 13. Further, the locking pawl 17 is biased clockwise by a spring 18 provided in the middle thereof.

A pin 19 fixed to a base plate (not shown) is provided near the top of the drive ring 6 in the drawing, and the toothed portion 6a of the drive ring 6
The end portion of the drive ring 6 or the stepped portion of the cam portion 6e comes into contact with the pin 19, thereby preventing excessive movement of the drive ring 6.

Reference numeral 21 denotes a photocoupler (optical detection means), and as shown in FIG. A light receiving section 21b receives light from the light projecting section 21a.
It has

Next, the effect will be explained. The rotation of the step motor is decelerated by the intermediate gear 4 from the gear 2 and transmitted to the toothed portion 6a of the drive ring 6, and the drive ring 6 first rotates counterclockwise in FIG. 1. Then, 2 of drive ring 6
The distance ring 7 also rotates integrally in the same direction as the drive ring 6 when the contact portion 6d at the end of the elongated hole pushes the pins 7a and 7b, and at this time, the ratchet teeth 7e of the distance ring 7 also rotate. They are sent in the same direction (forward direction) (Figure 2).

Immediately after the distance ring 7 starts rotating in this manner, its switch actuating section 7d moves away from the return detection switch 11 to turn it on, thereby inputting a rotation start signal to a control circuit (not shown).

The distance ring 7 rotates around the optical axis 5 to move a lens portion (not shown) in the axial direction of the optical axis 5, and drives the step motor for a predetermined pulse period based on the goldfish signal input by the control circuit. By doing so, the drive ring 6 is rotated so that the lens section moves a predetermined amount to the position where the lens is in focus (T-T, P-P in Fig. 5).
2).

When this focusing operation is completed, the control circuit immediately reverses the step motor to rotate the drive ring 6 in the opposite direction (clockwise direction).

After this reversal starts, the ratchet 1-tooth 7 of the distance ring 7
One of the lenses (e) is engaged with the pawl portion 13a of the ratchet pawl 13, preventing rotation of the distance ring 7 in the opposite direction (clockwise direction) and holding the lens portion at the current focusing position.

Therefore, only the drive ring 6 rotates clockwise against the spring 8, and its shaft portions 6b and 6c also rotate in the same direction.

In this way, when the drive ring 6 rotates relative to the distance ring 7, the pin 7a of the distance ring 7.

7b is stopped and the shafts 6b, 6c of the drive ring 6 are rotated, so that the operating holes 9a, 10a of the sectors 9.10 are stopped, and the sectors 9, which are supported by the shafts 6b, 6c of the drive ring 6, are rotated. , 10 are rotated, and the sectors 9 and 10 are rotated to open and close the shirt opening 20.

That is, when the shirt opening 20 opens by a predetermined amount as shown in FIG. 3 based on the exposure detection signal inputted to the control circuit (T1 to T2°P2 to P1 in FIG. 5), the shutter opening 20 is controlled by the control circuit. The step motor immediately reverses, causing drive ring 6 to rotate in the opposite direction (counterclockwise) and sector 9 .
10 closes the shirt opening 20 (T-T3 in FIG.
゜P −P2).

■ Even after the sectors 9 and 10 close the shutter opening 20, the drive ring 6 continues to rotate counterclockwise, and eventually its abutting portion 6d pushes the pins 7a and 7b, causing the distance ring 7 to be rotated again into the drive ring. 6 and the ratchet teeth 7e of the distance ring 7 are also sent in the same direction.

The ratchet tooth 7e portion is the pawl portion 1 of the ratchet pawl 13.
3a is sent in the same direction while finely moving up and down, and finally, the cam portion 7C lifts the pawl portion 13a higher than before and rotates the ratchet pawl 13 largely clockwise against the spring 14. Therefore, the locking pawl 17 is attached to the spring 1.
As shown in FIG. 4, the locking portion 13 of the ratchet pawl 13 is biased clockwise by
The locking pawl 17 rotates clockwise so that the pawl 17a locks on the upper surface of the ratchet pawl 13, and the pawl 13a of the ratchet pawl 13 is separated from the ratchet teeth 7e and maintains its position (see T-T, P-P in Figure 5).

Immediately before the claw portion 17a and the upper surface of the locking portion 13b engage with each other, the lower surface of the locking portion 13b contacts the claw position detection switch 15 to turn it off.

Therefore, the distance ring 7 can be rotated clockwise together with the drive ring 6, and the distance ring 7 is rotated clockwise by the step motor that reverses itself under the control of the control circuit that receives the OFF signal from the pawl position detection switch 15. At the same time, it rotates clockwise and returns to the initial position (T-T, P-Po in FIG. 5).

By the way, just before the distance ring 7 returns to the initial position, the switch actuating portion 7d of the distance ring 7 contacts the return detection switch 11, turns the return detection switch 11 OFF, and sends a return signal (OFF signal) to the control circuit. input and the sequence cycle returns to its initial state.

Similarly, just before the distance ring 7 returns to the initial position, the cam portion 6e of the drive ring 6 presses the pin portion 17b and rotates the locking pawl 17 in the counterclockwise direction. The portion 17a is the locking portion 1 of the ratchet pawl 13.
3b, the ratchet pawl 13 is rotated counterclockwise by the spring 14, and its pawl portion 13a is engaged with the ratchet tooth 7e of the distance ring 7 at the initial position (first
figure). Therefore, the lower surface of the locking portion 13b of the ratchet pawl 13 is separated from the pawl position detection switch 15, turning it on.
The claw position detection signal is also input to the control circuit.

Next, detection of the operation (movement) of the drive ring 6 and distance ring 7 by the photocoupler 21 will be explained.

As mentioned above, during the focusing operation of the lens section, the drive ring 6 and the distance ring 7 are integrally driven at To-TI in FIG. 5, and at this time, the holes 6f and 7f are formed as shown in FIG. Move together while maintaining the same positional relationship. Therefore, the light projected from the light projecting section 21a of the photocoupler 21 toward the light receiving section 21b can pass only through the holes where the holes 7f and 6f overlap, and therefore the holes are arranged at the pitch of the holes 7f. The detected pulse waveform is the seventh
T in the diagram. -It becomes like T1.

By driving the step motor for a predetermined period of pulses based on the goldfish signal inputted by the control circuit, the drive ring 6 is rotated so that the lens part moves a predetermined amount to the position where the lens is in focus, as described above. Reverse the step motor and move the drive ring 6 in the opposite direction (clockwise direction)
At this time, one of the ratchet teeth 7e of the distance ring 7 is engaged with the pawl portion 13H of the ratchet pawl 13.

At this time, since the pitch of the holes 7f is configured to be an integral multiple of the pitch of the ratchet teeth 7e, no matter which one of the ratchet teeth 7e is locked, the light emitting part 21 of the photocoupler 21
The light projected from a toward the light receiving part 21b can always pass through any of the holes 7f, and the distance ring 7 will not stop at any place other than the hole 7f and block the light from the photocoupler 21.

Next, when the exposure operation is performed based on the exposure detection signal, the drive ring 6 is driven forward and backward between T-T3 in FIG. 5, but at this time the distance ring 7 is stopped. , the hole 7f also stops, and therefore the photocoupler 21 detects only the hole 6f of the drive ring 6 and detects the hole at the pitch of the hole 6f, so the detection pulse waveform is Tl in FIG.
~It will look like T3.

After the exposure operation is completed, the reset operation is performed next (T3 to T5 in FIG. 5), but at this time, as described above, the drive ring 6 and distance ring 7 move together, so
Photocoupler 2 as in the case of T ”” T t in the figure.
The light of No. 1 can pass only where there are holes 7f, so the photocoupler 21 detects the holes at the pitch of the holes 7f, and the detection pulse waveform becomes like T-T5 in FIG.

Further, at T4 to T5 in FIG. 5, the claw portion 17a of the locking claw 17 is locked to the upper surface of the locking action portion 13b of the ratchet claw 13 as described above, and the claw portion 13a of the ratchet claw 13 is locked.
Since the drive ring 6 and the distance ring 7 are separated from each other so that they do not engage with the ratchet teeth 7e, the drive ring 6 and the distance ring 7 can move together, but in the unlikely event that an abnormal operation occurs, the engagement portion 13b of the ratchet pawl 13 may When the claw portion 17a of the locking claw 17 is released from the upper surface, the claw portion 13a of the ratchet claw 13 is engaged with the ratchet teeth 7e, and the movement of the distance ring 7 is stopped.

Under such a situation, the photocoupler 21 detects the holes at the pitch of the holes 6f of the drive ring 6 in the same way as T1 to T3 in FIG. 5, and the detection pulse waveform is as shown in T1 to T3 in FIG.
T3, the control circuit that receives the sudden change in the detection pulse can immediately stop the step motor to prevent the sectors 9 and 10 from opening the shutter opening 20 at the time of reset.

In the above embodiment, each moving member is configured to rotate around the shirt opening, but the drive ring and the distance ring may be configured as members that reciprocate linearly.

Further, in the above embodiment, ratchet teeth were formed on the outer periphery of the distance member, but considering the degree of freedom of arrangement within the shell, as described in Japanese Patent Application Laid-Open No. 62-200337, It is preferable to provide a gear on the outer periphery of the distance member, and to provide a pinion that meshes with the gear together with ratchet teeth, and it goes without saying that the present invention may also be configured in this manner.

Further, in the above embodiments, a helicoid type (spiral type) movement of the lens portion has been described, but a linear movement type in which the lens portion moves straight in the axial direction by a cam may be used.

Furthermore, in the above embodiments, the present invention has been described as being applied to an automatic focus/exposure operating device of a camera. The present invention may also be used.

Furthermore, in the above embodiments, the case where there are two moving members has been described, but the number of moving members is not limited to two and may be more.

Furthermore, in the above embodiment, the case where the multiple holes of the - moving member are opened at twice the pitch of the multiple holes of the other moving members is explained, but such a pitch does not need to be limited to twice. do not have.

FIG. 1 is a front view showing an initial state of the automatic focus/exposure operating device of a camera in which the present invention is used, and FIGS. 2 to 4 each illustrate the operating state. 5 is a sequence characteristic diagram of automatic focus/exposure operation showing the relationship between the rotation amount of the drive ring, exposure amount, etc. and time; FIG. 6 is a sectional view taken along the ■-■ arrow in FIG. 1; FIG. 7 is a detection pulse waveform diagram corresponding to FIG. 5.

〔Effect of the invention〕

As explained above, according to the present invention, the integral motion of a plurality of moving members can be simultaneously detected or their relative motions can be detected separately using the same detection means. becomes possible. Therefore, the number of parts of the detection device is reduced, and it is possible to prevent the device from increasing in size, weight, cost, etc.

[Brief explanation of the drawing]

Figures 1 to 7 show mechanical motion detection 1 according to the present invention.
...Rotor shaft 2...Gear 3.12.16...Shaft 4...Intermediate gear 4a... Large diameter tooth section 4b... Small diameter tooth section 5... Optical axis 6... Drive ring (first moving member) 6a
...Tooth portions 5b, 5c, ...Shaft portion 6d...Abutting portion 6e...Cam portion 6r...Hole 7... ... Distance ring (second movement member) 7a
, 7b, 19...Pin 7C...Cam section 7d...Switch actuating section 7e...Ratchet tooth 7f...Hole 8. 1418... Spring 9.10... Sector (blade) 9a, 1
0a...Operating hole 11...Return detection switch 13...
...Ratchet pawl 13a...Claw portion 13b...Locking action portion 15...Claw position detection switch 17...
...Latching claw 17a...Claw portion 17b...Pin portion 20...Shutter opening 21...Photo Coupler (optical detection means)
21a...Light emitter 21b...Light receiver Patent applicant Seikosha Co., Ltd. Patent agent Kazuko Matsuda Rotation angle Figure 5 T. Figure 6 Figure 7

Claims (1)

[Claims] a first moving member having a plurality of holes opened at a predetermined pitch; an optical detection means for optically detecting the plurality of holes of the first moving member to detect movement of the first moving member; and the first moving member. a second moving member having a plurality of holes opened at a pitch that is an integral multiple of two or more of the plurality of holes, and arranged so that the plurality of holes can be detected together with the plurality of holes of the first moving member by the optical detection means. , the optical detection means detects the plurality of holes in the second moving member when the first moving member and the second moving member move integrally, and when the second moving member stops and the second moving member moves in unison, A mechanical motion detection device characterized in that a plurality of holes in a first moving member are detected when only the member moves.