JP3365794B2 - Driving force transmission mechanism - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving force transmission mechanism, and more particularly, to a driving force transmission mechanism for a camera for winding a film, rewinding a film, zooming a lens frame, etc. using a single motor. It is a thing.

[0002]

2. Description of the Related Art Conventionally, in a camera having a drive force transmission mechanism for driving a drive system for film winding, rewinding, zooming of a lens frame, etc. with a single motor, for example, a user It is known that a clutch for switching the rotational power of the motor to each drive system is switched by operating an operation button or an operation lever.

Further, Japanese Laid-Open Patent Publication No. 1-287547 discloses a drive control device for a camera which performs release, shutter charge, and section switching by forward rotation of a single motor, and film winding and film rewinding by reverse rotation. ing.

Further, Japanese Patent Application Laid-Open No. 3-81750 discloses an electric drive camera in which film winding and shutter charging are performed by forward and reverse rotations of a single motor, respectively.

Further, there is also one in which a dedicated motor for winding and rewinding the film is provided and a dedicated motor for zooming is provided to drive each drive system.

[0006]

Each of the above technical means requires a clutch portion for switching and transmitting the rotational power of the motor to each drive system, and is complicated in order to perform the switching operation of the clutch portion. Needed a special mechanism. In addition, this complicated mechanism hinders the further miniaturization of the camera, which has been desired more in recent years, and increases the cost due to the increase in the number of parts.

The present invention has been made in view of the above problems, and solves the above problems and enables driving by switching various driving systems with a single motor without using a complicated switching mechanism. An object is to provide a driving force transmission mechanism.

[0008]

In order to achieve the above-mentioned object, a first driving force transmission mechanism according to the present invention comprises a single motor, a sun gear which is normally and reversely rotated by this motor, and this sun gear. A plurality of planetary gears that always mesh with each other, prohibiting means for permitting revolution of the plurality of planetary gears around the sun gear due to rotation of the sun gear in one direction, and prohibiting revolution due to rotation in the other direction; When the planetary gears of the above are prohibited from revolving in the other direction of rotation of the sun gear, at least one is arranged on the revolution locus of the planetary gears so as to mesh with any of the plurality of planetary gears. A plurality of driven gears and the plurality of planetary gears are revolved by the rotation of the sun gear in one direction, and at least one of the driven gears that is meshed with at least one of the plurality of planetary gears is selected. ,other Control means for driving and controlling the sun gear that is normally and reversely rotated by the motor so that the driving force is transmitted to the selected driven gear through the planetary gear by the rotation in the opposite direction. Characterize.

In order to achieve the above object, the second driving force transmission mechanism according to the present invention is the first driving force transmission mechanism, wherein the control means selects the one of the plurality of planetary gears. It is characterized in that the rotation of the sun gear in one direction is controlled so that the driven gear close to the driven gear is meshed with the driven gear.

[0010]

In the first driving force transmission mechanism according to the present invention, the plurality of planetary gears are revolved by the rotation of the sun gear in one direction, and at least one of the plurality of planetary gears meshes with the above-mentioned gear. Driving at least one of the driving gears and driving the sun gear, which is normally and reversely rotated by the motor, so as to transmit the driving force to the selected driven gear through the planetary gears by rotation in the other direction. Control.

A second driving force transmission mechanism according to the present invention is the first driving force transmission mechanism, wherein one of the plurality of planetary gears closest to the selected driven gear is the driven gear. The unidirectional rotation of the sun gear is controlled so as to be meshed with.

[0012]

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

Prior to describing the embodiment of the present invention, a reference example which is a premise of the embodiment will be described with reference to FIGS. 1 to 8.

FIG. 1 is an enlarged perspective view showing an example of a driving force transmission mechanism which is a premise of an embodiment of the present invention.

FIG. 2 is an enlarged plan view of the main part of the driving force transmission mechanism shown in FIG. 1 viewed from above.

The motor 1 is a motor that has a pinion 2 on its output shaft and is rotatable in the forward and reverse directions. The pinion 2 meshes with the gear 11 via a reduction gear train (not shown), and transmits the turning force of the motor 1 to the gear 11. On the upper part of the gear 11, a sun gear 12 having a common support shaft is integrally formed.

The ratchet wheel 15 has a thick disk shape and is provided with notches 15f at four symmetrical positions. One side wall of the cutout portion 15f forms a vertical wall 15c, and the other side wall forms a cam surface 15b which is tapered downward.

A cylindrical insertion hole 15d is formed at the center of the ratchet wheel 15, and a cylindrical portion 15e having the same inner diameter as the insertion hole 15d is formed at the center of the upper surface of the ratchet wheel 15. It is vertically installed integrally with the ratchet wheel 15. The sun gear 12 is rotatably fitted in the insertion hole 15d and the cylindrical portion 15e. The cylindrical portion 15e has a notch formed in a part of its peripheral surface, and the sun gear 12 fitted therein is vertically provided at a position facing the notch near one end of the upper surface of the ratchet wheel 15. Pin 15a
It is adapted to mesh with a planetary gear 13 rotatably attached to the planetary gear 13.

The planetary gear 13 and the upper surface of the ratchet wheel 15 have some friction (not shown).
Since it also has a mesh with the sun gear 12 as described above, the ratchet wheel 15 also rotates in the direction in which the sun gear 12 rotates.

As shown in FIG. 2, a shaft 20 is provided at a position which is horizontally equidistant from the sun gear 12 and which is opposed to each other.
The shaft 40 and the shaft 30 and the shaft 50 (not shown in FIG. 1) are vertically provided. Drive system gears 21, 31, 41, and 51 are axially mounted on the shafts 20, 30, 40, and 50, respectively. Each of these drive system gears is connected to various drive systems as described later and serves as a drive source for these.

Internal gears 17 are arranged between the gears 21, 31, 41 and 51 adjacent to each other.

Notch 15 of the ratchet wheel 15
A click stopper 60 is vertically provided from below at a location on the rotation arc of f (see FIG. 2).

3 and 4 show the click stopper 6
FIG. 6 is a development view in which the ratchet wheel 15 is circumferentially developed at the center of 0. 3 shows the relationship between the ratchet wheel 15 and the click stopper 60 when the planetary gear 13 is meshed with the drive system gear 21 as shown in FIG. 2, and FIG. Planetary gear 13
Shows the relationship between the ratchet wheel 15 and the click stopper 60 when located between the drive system gear 21 and the gear 31 for example.

The click stopper 60 is held by a guide holder 61 so as to be slidable in the vertical direction, and is urged upward by a spring 63 arranged between a pedestal 62 and the lower surface of the click stopper 60. ing. Then, when the ratchet wheel 15 rotates and the click stopper 60 reaches the cutout portion 15f, the ratchet wheel 15 is pushed upward by the biasing spring 63.

When the sun gear 12 rotates in the CW direction (see FIG. 1), the planetary gear 13 revolves clockwise, whereby the ratchet wheel 15 also rotates in the same direction, that is, in the direction of arrow M1 in FIG. To do. However,
Since the click stopper 60 comes into contact with the hanging wall 15c, the rotation of the ratchet wheel 15 in the M1 direction is restricted by this. If this restriction position is set to a position that meshes with any of the drive system gears 21, 31, 41, 51, the rotational force of the sun gear 12 is transmitted through the planetary gear 13 to the drive gears 21, 31, 41, 5
Can be transmitted to 1.

On the other hand, when the sun gear 12 rotates in the CCW direction (see FIG. 1), the planetary gear 13 revolves counterclockwise, which causes the ratchet wheel 15 to rotate in the same direction, that is, as indicated by an arrow M2 in FIG. Rotate in the direction. At this time, the click stopper 60 is attached to the cam surface 15b.
While coming into contact with the lower surface of the ratchet wheel 15 (the state shown in FIG. 4), the next notch 15f is reached. At this time, the planetary gear 13 revolves counterclockwise from the state in which it meshes with the drive gear 21 in FIG. 2 and further revolves while meshing with the internal gear 17 to form a two-dot chain line 13a in the figure. Move from the position indicated by to the position slightly revolved counterclockwise. As described above, when the sun gear 12 rotates in the CW direction, the sun gear 12 returns to the position indicated by 13a in the figure and surely meshes with the drive gear 31, thereby transmitting the rotational force of the sun gear 12 to the drive system gear 31. To do. Further, by rotating the sun gear 12 in the CCW direction, 13b in the figure
Alternatively, the planetary gear 13 can be located at the position 13c.

The revolving position of the planetary gear 13 is such that the reflector 19 that rotates integrally with the ratchet wheel 15 is detected by a PR (photo reflector) or the like (not shown).

The reflector 19 has four blades 19a, 19b, 1 extending outward by cutting out four symmetrical positions.
9c, 19d is a disk shape having a circular hollow portion, and the circular hollow portion is the ratchet wheel 1
5 is arranged so as to be fitted on the upper portion of a cylindrical portion 15e vertically provided at the center of the upper surface of 5. The above four blades 19a, 19
Of the b, 19c, and 19d, the blade 19a has a width that is about 1/3 narrower than the other three blades.

When the reflection plate 19 rotates in conjunction with the ratchet wheel 15, the blades 19a, 19b, 19c, 19d are referenced with reference to the short signal obtained from the blade 19a by the PR arranged at a predetermined position. Detect the position of. Then, the planetary gear 13 is revolved to a position where it meshes with the drive system gears 21, 31, 41, 51 to be connected.

Further, the drive system gears 21, 31, 4
Gear trains (not shown) connected to drive systems for zooming down the lens frame, zooming up the lens frame, film winding, and film rewinding are connected to the motors 1, 51, respectively. Each drive system operates by the rotation of.

Summarizing the above, 1) By the motor 1,
Rotate the sun gear 12 in the CCW direction (see Fig. 1),
The planetary gear 13 is moved to a position where it meshes with the drive system gear of the drive system to be driven. This position is detected by the photo reflector or the like. ... Drive system selection operation.

2) The sun gear 12 is moved to C by the motor 1.
By rotating in the W direction (see FIG. 1) and rotating the planetary gear 13, the drive system gear of the drive system you want to drive,
Power is transmitted through the planetary gear 13. ... Transmission of driving force to the drive system.

FIG. 5 is an electric circuit diagram showing the electrical construction of the driving force transmission mechanism shown in FIG.

In the figure, a switch 1R connected to the CPU,
2R, BK, ZU, ZD, 1K are respectively 1R: First release switch or timing switch for photometry / distance measurement 2R: Second release switch or exposure switch BK: Back cover open / close detection switch ZU: Zoom up switch ZD: Zoom down switch 1K: a film feed amount detection switch, and the CPU drives a motor M or the like by controlling an interface IC (IF-IC) having a built-in motor driver via a bus based on signals from these switches. To do. In addition, the planetary gear 13 is included in the IF-IC.
An optical sensor such as a photo-reflector PR for detecting the position of is connected, and an output signal from the optical sensor is input. Then, the motor M is driven under the control of the CPU.

Next, a method of controlling the position of the planetary gear 13 will be described with reference to the flowchart of FIG.

First, after resetting the battery, the motor 1
To rotate the sun gear 12 in the CCW direction (see Fig. 1)
To rotate (step S101). Next, the rising pulse of the photo reflector PR is detected (step S1
02), the timer in the CPU is started (step S103). Then, the falling pulse of the photo reflector PR is detected (step S104), and the reading of the timer is started (step S105). When the timer reaches a predetermined time A (step S106), the motor 1 is braked (step S107), the reset position is memorized (step S108), and the process returns to the main routine.

Next, the zoom-up operation of each drive system will be described with reference to the flow chart shown in FIG.

First, the current position of the planetary gear 13 is checked by the photo reflector PR or the like to determine whether or not it is at the position 13b (see FIG. 2) in which the drive system gear 31 for zooming up is engaged (see FIG. 2). Step S111). If the position is not 13b, the motor 1 is rotated to rotate the sun gear 12 in the CCW direction (step S112). When the rising pulse of the photo reflector PR is detected (step S113), the position count-up is started (step S114). After that, when the planetary gear 13 reaches the position 13b where the planetary gear 13 meshes with the zoom-up drive system gear 31 (step S11
5) Apply the brake to the motor 1 (step S11
6) and proceeds to step S117.

After the planetary gear 13 is positively engaged with the zoom-up drive system gear 31, the motor 1 is then driven.
In the CW direction (see FIG. 1) to rotate the sun gear 12 in the CW direction to drive the zoom-up drive system gear 31 via the planetary gear 13 (step S1).
17). Thereafter, the zoom-up switch ZU is checked (step S118), and when the zoom position reaches a desired zoom position, the motor 1 is stopped to end the zoom-up operation (step S119), and then the process returns to the main routine.

In the example of the driving force transmission mechanism shown in FIG. 1, the above-mentioned drive systems are set to wind up and rewind the film, zoom up and zoom down the lens frame. However, the invention is not limited to this, and for example, a shutter can be used. It is also suitable for driving, opening and closing the barrier, extending and retracting the autofocus lens, moving the strobe, and switching panoramic shooting screens.

Next, another example of the driving force transmission mechanism, which is a premise of the embodiment of the present invention, will be described.

FIG. 8 is a plan view showing another example of the driving force transmission mechanism which is the premise of the embodiment of the present invention.

In FIG. 8, the pinion 2 is an output pinion of the motor 1 (not shown) capable of rotating in the forward and reverse directions. The pinion 2 meshes with a reduction gear train (not shown), and transmits the rotational power of the motor 1 to the sun gear 11.

The planetary gear 13 meshes with the sun gear 11 and is connected by a gear arm 12. When the sun gear 11 rotates in the CCW direction in the figure, the planet gear 13 is C with the center axis 11a of the sun gear 11 as the center.
It revolves in the CW direction and further revolves while meshing with the internal gear 17.

While the planetary gear 13 revolves, the support shaft 13a of the planetary gear 13 advances while pushing one end 160a of the bifurcated tip of the stopper 160 having the shaft 61 as the center of rotation, and is attached to the stopper 160. The direction of the force of the toggle spring 162 is changed and the stopper 160 is moved to the fulcrum 16
Push up around 1 to the position indicated by the chain double-dashed line. As a result, the planetary gear 13 meshes with the gear 65 and transmits the turning force of the motor 1 to the gear 65. A pin 65a is vertically provided on the gear 65.
The a is adapted to be fitted into the long hole 70a of the arm 70 having the rotation center at 71.

The arm 70 has an L-shaped bent portion on the base end side, and the bent portion has a plurality of holes 70c,
70c 'are continuously provided. The width of the perforation hole 70c 'is about twice the width of the other three perforation holes 70c. The photo interrupter PI is arranged at a position facing each other with the transfer path of the hole 70c interposed therebetween. The tip of the arm 70 forms a bifurcated portion 70b, and the pin 16a is provided so as to extend vertically from the planetary gear 16.
Are engaged. And the sun gear 11 is CCW
When the gear 65 rotates in the CCW direction,
The pin 65a causes the arm 70 to reciprocate around a fulcrum 71 as a center of rotation. As a result, the planetary gear 16 can be arranged at a position where it meshes with each of the drive system gears 21, 31, 41, 51.

A hole 70 is formed in the photo interrupter PI.
The arm 70 is formed by each hole 70c with c'as a reference position.
When the arm 70 moves to a position where the planetary gear 16 meshes with a desired drive system gear, the motor 1 is rotated in the reverse direction to rotate the sun gear 11 in the CW direction. Then, when the sun gear 11 rotates in the CW direction, the planetary gear 13 starts to revolve in the CW direction around the shaft 11a and further revolves while meshing with the internal gear 17.

During the revolution of the planetary gear 13, the support shaft 13a of the planetary gear 13 is connected to the tip portion 160 of the stopper 160.
While pushing b, the direction of the force of the toggle spring 162 is changed to move the stopper 160 to the position shown in the figure. As a result, the base end surface of the stopper 160 contacts the peripheral surface of the gear 65, and the rotation of the gear 65 is locked. Further, when the sun gear 11 rotates in the CW direction, the planet gear 13 is separated from the internal gear 17 and meshes with the gear 14.

Since the gear 14 is attached to the fixed shaft 14a and the gear 14 and the planetary gear 16 are connected by the gear arm 15, the rotational force of the sun gear 11 is transferred to the planetary gear 13, Gear 14, planetary gear 1
6, the drive system gears 21, 31, 4 selected previously
1 or 51.

In summary, 1) the motor 1 rotates the sun gear 11 in the CCW direction to move the planetary gear 16 to a position where it meshes with the drive system gear of the drive system to be driven. This position is detected by the photo interrupter or the like. ... Drive system selection operation.

2) The sun gear 11 is moved to C by the motor 1.
By rotating in the W direction and rotating the planetary gear 16, power is transmitted to the drive system gear of the drive system to be driven via the planetary gear 16. ... Transmission of driving force to the drive system.

Next, the driving force transmission mechanism of the first embodiment of the present invention will be described.

FIG. 9 is a plan view of the driving force transmission mechanism showing the first embodiment. In addition, FIG. 10 shows A in FIG.
FIG. 6 is a cross-sectional view of an essential part of the driving force transmission mechanism showing the first embodiment, showing the section A.

As shown in FIG. 10, a pinion 101a is attached to the output shaft of a motor 101 capable of rotating in the normal and reverse directions, and the pinion 101a transmits the rotational power of the motor 101 through a reduction gear train (not shown). It is designed to be transmitted to 102. On the upper surface of the gear 102, a disc-shaped spacer 102b that determines a rotation center position of a ratchet wheel 103 described later is provided integrally with the gear 102. A gear 102a that rotates integrally with the gear 102 is coaxially provided on the upper surface of the spacer 102b. Spindle pins 103a and 103a 'are vertically provided on both side edges of the upper surface of the ratchet wheel 103 which are symmetrical to each other. The planetary gears 10 are respectively attached to the spindle pins 103a and 103a'.
4, 104 'are rotatably mounted on the gear 102a. Further, both the planetary gears 104 and 104 ′ have a slight friction 105 with the ratchet wheel 103.

When the gear 102 rotates, the gear 1
The gear 102a formed integrally with 02 rotates,
As a result, the planetary gear 104 meshed with the gear 102a also rotates, so that the ratchet wheel 10
A turning force is generated in 3 in the direction in which the gear 102a rotates.

As shown in FIG. 9, the ratchet wheel 103 is provided with eight claws of the same type having a peripheral end face 103d and one claw having a peripheral end face 103e longer than the claws. Further, in the vicinity of the outer peripheral portion on one side of the ratchet wheel 103, the ratchet wheel 10
A non-return lever 110 for controlling the rotation of the No. 3 is provided. This non-return lever 110 has its fulcrum as a support shaft 110d.
The one-arm end 110c is pivotally mounted on the one end and is formed with a check claw 110e that engages with the claw. Further, a spring 111 is installed between one arm end of the check lever 110 and a predetermined position in the camera body, and biases the check lever 110 toward the ratchet wheel 103. The one-arm end portion 110c swings to a position where it abuts on the locking portion 112 by the urging force of the spring 111, and the check claw 110e is attached to the ratchet wheel 1.
03 The engagement surface 103b of the claw portion is engaged.

In the vicinity of one side of the ratchet wheel 103, the drive gear 12 is circumferentially provided at a predetermined interval corresponding to the interval of the claw portions of the ratchet wheel 103.
0, 121, 122, 123, and 124 are mounted on a shaft (not shown). In addition, the planetary gear 10
4, 104 'revolve around the rotation of the gear 102a, but when the check claw 110e engages with a predetermined locking surface 103b of the ratchet wheel 103 claw portion, the drive gear 120, 121, 122, 12
It is adapted to mesh with any one of 3,124. The drive gears 120, 121, 122, 1
Reference numerals 23 and 124 are connected to a film winding mechanism, a film rewinding mechanism, an autofocus mechanism, a zoom down mechanism, and a zoom up mechanism via gear trains (not shown), respectively, and are drive sources thereof.

When the gear 102a rotates in the direction of arrow CCW in the figure, the ratchet wheel 103 also rotates in the same CCW direction as the planetary gears 104 and 104 'revolve. Here, when the force of the friction 105 is set to be stronger than the biasing force of the spring 111, the check lever 110 has the check claw 110e.
The ratchet wheel 103 is pushed upward by the inclined surface 103c of the claw portion against the biasing force of 11,
Swing to the position indicated by the chain double-dashed line. Then, the ratchet wheel 103 is rotated by the ratchet mechanism.

Then, the rotation mechanism of the ratchet wheel 103 is controlled by a control mechanism (which will be described later) based on the swinging motion of the check lever 110, whereby the positions of the planetary gears 104 and 104 'on the revolution locus. It becomes possible to control. That is, the planetary gears 104, 104 'are stopped at desired positions, and the drive gears 120, 12' are
The revolution operation of the planetary gears 104, 104 'can be controlled so as to mesh with any one of 1, 122, 123, 124.

After the planetary gears 104, 104 'are selected by meshing with any of the drive gears 120, 121, 122, 123, 124, the gears 102 are then selected.
When a is rotated in the direction of arrow CW in the drawing, a rotational force that rotates in the same CW direction is generated in the ratchet wheel 103, but the check claw 110e engages with the locking surface 103b of the claw of the ratchet wheel 103. The ratchet wheel 103 is restrained from rotating because it is aligned, and remains stopped. The rotational force of the gear 102a is transmitted through the planetary gear 104 or the planetary gear 104 'to the drive gears 120, 121, 122, 123, 12
4 is transmitted.

Next, a control mechanism based on the swing motion of the check lever 110 will be described.

A reflection plate 110a is attached to the other arm end of the check lever 110, and a PR (photoreflector) 150 is provided at a predetermined position in the thrust direction on the swing locus of the other arm end. Is provided. When the check lever 110 swings to the position shown by the chain double-dashed line in the drawing, the PR 150 detects the other arm end of the check lever 110.

FIG. 11 shows the ratchet wheel 10 described above.
3 is a time chart showing the operation of the check lever 110 and the output signal of the PR 150.

In the figure, the reference numerals indicating the state of the ratchet wheel 103 are: Wind: film winding RW: film rewinding AF: auto focus ZD: zoom down ZU: zoom up, and the above states are respectively the above driving conditions. Gear 120,
It corresponds to 121,122,123,124. That is, the ratchet wheel 103 rotates, and either of the planetary gears 104 and 104 'is driven by the drive gear 1.
It meshes with any one of 20, 121, 122, 123, and 124 to select any one of the above states.

Further, as described above, since only one of the nine claws of the ratchet wheel 103 has a peripheral end surface longer than the other claws, the ratchet wheel 103 is shown in FIG. When rotated in the CCW direction, the PR 150 outputs eight short ON signals (pulse signals) and one long ON signal (pulse signal).

In the first embodiment, from the fall of the one long ON signal to the fall of the eighth ON signal,
That is, the state in which the planetary gear 104 shown in FIG. 9 is in mesh with the drive gear 122 connected to the autofocus drive mechanism is the initial position.

FIG. 12 shows the PR relating to the initial position setting of the ratchet wheel 103 in the first embodiment.
It is an output signal time chart of 150.

The pulse signal (denoted by CPO in the figure) output from the PR 150 is skipped at the timing T1 in the figure immediately after the start. In addition,
The number of pulses is based on the data (GPSTRT) stored in an EEPROM or the like (not shown). Next, in the figure, the pulse signal is counted by the pulse number counter C1 at timing T2 and becomes a drive sequence signal of one cycle. In the figure, the ON signal section indicated by max indicates that the one long ON signal is output. Further, in the figure, the ratchet wheel 103 is moved to the position corresponding to the autofocus drive gear 122 by the pulse signal at the timing T3, that is,
The planetary gear 104 is moved to a position where it meshes with the drive gear 122.

13 and 14 show the ratchet wheel 103 (planetary gears 104, 10) in the first embodiment.
4 ') is a flowchart showing a subroutine of an initial position setting operation of 4'). Note that these flowcharts will be described as operations of a CPU (not shown).

In the initial position setting operation of the ratchet wheel 103, and by extension, the planetary gears 104 and 104 ', first, the motor drive voltage is set (step S120), and the motor 101 (see FIG. 10) is driven (step S1).
21), EEPR which does not show the skipped pulse number C0
The value stored in the OM or the like is set (step S12).
2). At this time, the flag F1 = 1. afterwards,
Set the pulse number counter C1 = 8 (step S12
3) The process waits until the falling edge (Low edge) of the pulse signal is detected (step S124). When the fall of the pulse signal is detected in step S124,
The pulse width timer T0 starts (step S12
5), falling of the pulse signal (High edge)
A hard timer of a CPU (not shown) is activated until is detected (step S126). That is, the pulse width is detected here.

When the rising edge of the pulse signal is detected in step S126, the pulse width output from the timer T0, that is, the PR150 is read (step S127), and the minimum pulse width data stored in the EEPROM or the like is read. (Step S128,
Step S129). When the pulse width output from the PR 150 is less than the minimum pulse width stored in the EEPROM or the like, it is determined that chattering has occurred, and the process returns to step S124.

Steps S128 and S129 described above
And the pulse width output from the PR150 is EE
When the pulse width is equal to or larger than the minimum pulse width stored in the PROM or the like, the flag F1 is checked to detect whether or not the reading is skipped (step S130). Here, if the reading skip is in progress, the reading skip pulse number C0 is decremented (step S131), and it is checked whether or not C0 = 0 (step S132). Then, in step S132, C ≠
If it is 0, directly, and if C0 = 0, skip reading ends (step S133), and the process returns to step S124.

When it is determined in step S130 that the skip has been completed, the process proceeds to [2] of FIG. 14 and the current pulse width from the PR 150 is compared with the past maximum value (step S134, step). S135). When the current pulse width is larger, the current pulse width is set to the maximum value (step S136), and the value of the pulse number counter C1 is stored in the RAM-1 area in the RAM (not shown) (step S137). The pulse number counter C1 is decremented (step S138).

When the current pulse width is smaller in step S135, the process proceeds to step S138,
Then, it is determined whether or not the pulse number counter C1 = 0 (step S139). If the pulse number counter C1 ≠ 0 in step S139, that is, if the one-cycle sequence shown in FIG. 12 is not completed,
In FIG. 13, the process proceeds to [1] and the above step S124.
Return to.

If the pulse number counter C1 = 0 in step S139, that is, if the one-cycle sequence shown in FIG. 12 is completed, the current position of the ratchet wheel 103 shown in FIG. 13 is calculated. Perform (step S140). That is, the absolute position of the ninth pulse is calculated from the position data of the maximum pulse width. That is, the position of max is set to the absolute position 4, as shown in FIG. When the data stored in the RAM-1 area + 4> 10, the first digit is the absolute position.
After that, the planetary gear 104 is driven to a position where it meshes with the autofocus drive gear 122 (step S14).
1). Then, the current position of the ratchet wheel 103 (planetary gears 104, 104 ') is stored in the RAM-2 area of the RAM (step S142), and the subroutine ends.

FIG. 15 is a flow chart showing a subroutine of the drive gear selecting operation in the first embodiment. Like the above flowchart, this flowchart will be described as an operation of a CPU (not shown).

In the drive gear selection operation, first, the target position data of the drive gear is stored in RAM-
The area A is set (step S151). After that, the motor drive voltage is set (step S152), and the RAM is
-Compare the data in the area A with the data in the RAM-2 area (step S153, step S154). That is, the target position of the drive gear is compared with the current position of the ratchet wheel 103 or the planet gears 104, 104 '. Then, when the planetary gears 104, 104 ′ reach the target position in step S154, the motor 101 (see FIG. 10) is braked and stopped (step S160).

If the planetary gears 104, 104 'have not yet reached the target position in step S154, the motor 101 is further driven (step S1).
55), the fall of the pulse from the PR150 (L
until the ow edge) is detected, the planetary gears 104, 10
4'is revolved (step S156).

When the trailing edge of the pulse is detected in step S156, the motor drive voltage is reset (step S157), and it is determined whether the leading edge of the pulse is detected (step S158). Then, the data in the RAM-2 area is incremented (step S159), and the process returns to step S153.

Next, the driving force transmission mechanism of the second embodiment of the present invention will be described.

The drive force transmission mechanism of the second embodiment is basically the same as that of the first embodiment, except for the drive gear selecting operation. Therefore, the description of the equivalent portions will be omitted.

In the case of the first embodiment, the planetary gear 10
One of the 4, 104 'is moved to a position where it meshes with the drive gear of the drive system to be driven. However, in order to reduce the time lag during the switching operation, it is preferable to mesh the planet gear closer to the gear to be driven. This point is taken into consideration in the second embodiment, and the control sequence in this case will be described with reference to the flowchart of FIG.

In the drive gear selection operation, first, the first target position data D1 of the drive gear is set in the RAM-A area in the RAM (not shown) (step S151). Next, the second target position data D2 is set in the RAM-B (step S151 '). After that, the motor drive voltage is set (step S152), and the data in the RAM-A area is compared with the data in the RAM-2 area shown in the flowchart of FIG. 14 (steps S153 and S154). That is, the first target position data D1 of the drive gear is compared with the current position data of the ratchet wheel 103 or the planet gears 104, 104 '. When the planetary gears 104, 104 'reach the first target position in step S154, the motor 101 is braked and stopped (step S160).

When the RAM-A and the RAM-2 are not equal to each other, the data in the RAM-B area and the data in the RAM-2 area are compared (steps S153 'and S154'). That is, the second target position data D2 of the drive gear and the ratchet wheel 103 or the planetary gear 104,
The current position data of 104 'is compared. Then, in step S154 ', the planetary gears 104, 10 are
When 4 ′ reaches the second target position, the motor 101
Brake to stop (step S160).

If the planetary gears 104, 104 'have not yet reached the target positions in step S154', the motor 101 is further driven (step S154 ').
155), until the trailing edge (Low edge) of the pulse from the PR 150 is detected,
104 'is revolved around (step S156).

When the trailing edge of the pulse is detected in step S156, the motor drive voltage is reset (step S157), and it is determined whether the leading edge of the pulse is detected (step S158). Then, the data in the RAM-2 area is incremented (step S159), and the process returns to step S153 '.

By such control, the planetary gear 10
The time lag until 4,104 'meshes with the drive gear is reduced.

The first and second embodiments described above are summarized as follows: 1) The gear 102a is rotated in the CCW direction by the motor 101, and the planetary gears 104, 104 'are positioned at the positions meshing with the drive gears of the drive system to be driven. Move one of them. This position corresponds to the photo reflector PR15.
It is detected by the output signal from 0. ... Drive system selection operation.

2) The gear 102a is driven by the motor 101.
Is rotated in the CW direction, and the planetary gear 104 or the planetary gear 104 'is used as the drive gear of the drive system to be driven.
Power is transmitted via. ... Transmission of driving force to the drive system.

[0090]

As described above, according to the present invention, it is possible to provide a driving force transmission mechanism that enables driving by switching various driving systems with a single motor without using a complicated switching mechanism.

[Brief description of drawings]

FIG. 1 is an enlarged perspective view showing an example of a driving force transmission mechanism that is a premise of an embodiment of the present invention.

FIG. 2 is an enlarged plan view of a main part of the driving force transmission mechanism shown in FIG. 1, viewed from above.

FIG. 3 is a development view in which a ratchet wheel is circumferentially expanded at the center of a click stopper in the driving force transmission mechanism shown in FIG.

FIG. 4 is a development view in which a ratchet wheel is circumferentially developed at the center of a click stopper in the driving force transmission mechanism shown in FIG. 1.

5 is an electric circuit diagram showing an electrical configuration of the driving force transmission mechanism shown in FIG.

6 is a flowchart showing a method for controlling the position of a planetary gear in the driving force transmission mechanism shown in FIG.

7 is a flowchart showing a zoom-up operation of each drive system in the drive force transmission mechanism shown in FIG.

FIG. 8 is a plan view showing another example of the driving force transmission mechanism which is a premise of the embodiment of the invention.

FIG. 9 is a plan view of the driving force transmission mechanism showing the first embodiment of the present invention.

FIG. 10 is a sectional view of the main part of the driving force transmission mechanism showing the first embodiment, showing the AA cross section in FIG. 9;

FIG. 11 is a time chart showing the operation of the ratchet wheel, the check lever and the output signal of the photo reflector in the first embodiment.

FIG. 12 is a time chart showing an output signal of the photo reflector in setting the initial positions of the ratchet wheel and the planetary gear in the first embodiment.

FIG. 13 is a flow chart showing a subroutine of an initial position setting operation of the ratchet wheel and the planetary gear in the first embodiment.

FIG. 14 is a flowchart showing a subroutine of an initial position setting operation of a ratchet wheel and a planetary gear in the first embodiment.

FIG. 15 is a flowchart showing a subroutine of a drive gear selection operation in the first embodiment.

FIG. 16 is a flowchart showing a subroutine of a drive gear selection operation in the second embodiment of the present invention.

[Explanation of symbols]

1 ... Motor 2 ... Pinion 12 ... sun gear 13 ... Planetary gear 15 ... Ratchet wheel 17 ... Internal gear 21, 31, 41, 51 ... Drive system gear 60 ... Click stopper

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Claims (2)

(57) [Claims] 1. A single motor, a sun gear that is normally and reversely rotated by the motor, a plurality of planetary gears that constantly mesh with the sun gear, and a plurality of planetary gears in one direction of the sun gear. Prohibition means for permitting revolution around the sun gear due to rotation and prohibiting revolution due to rotation in the other direction, and at least one of the plurality of planet gears when the revolution due to rotation in the other direction of the sun gear is prohibited. A plurality of driven gears arranged on the revolution path of the planetary gear so as to mesh with any of the plurality of planetary gears, and revolve the plurality of planetary gears by rotating the sun gear in one direction. And selecting at least one of the driven gears with which at least one of the plurality of planetary gears meshes,
Control means for driving and controlling the sun gear that is normally and reversely rotated by the motor so that the driving force is transmitted to the selected driven gear through the planetary gear by rotation in the other direction. A drive force transmission mechanism characterized by. 2. The control means controls rotation of the sun gear in one direction so that one of the plurality of planetary gears close to the selected driven gear is meshed with the driven gear. The driving force transmission mechanism according to claim 1, wherein: