JPH0234674Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a motor drive device for a camera, and more particularly to a frame speed conversion device thereof.

When taking continuous photographs using a motor drive device in a camera, if the frame speed of automatic film winding by the motor drive device can be freely changed,
By changing the frame speed as necessary depending on the shooting situation, it is possible to avoid taking unnecessary pictures and prevent unnecessary consumption of film.

However, changing the shooting frame speed is only possible with a motor drive device that has a frame speed conversion function, and it is necessary to purchase a motor drive device that has that function from the beginning.

On the other hand, depending on the picture to be taken, the frame speed conversion function becomes useless and becomes a burden on the motor drive device in terms of size, weight, and cost, resulting in inefficiency.

Therefore, in this invention, even if the motor drive device does not have a shooting frame speed conversion function from the beginning, the frame speed conversion function can be activated by using an external signal terminal that may be prepared for use for other purposes. By supplying a frame speed conversion device that enables continuous photography using a motor drive device, and by making the frame speed conversion device detachable from the motor drive device, it is possible to meet the needs of the photographer. The purpose is to make it available for purchase or use.

FIG. 1 shows the external appearance of an embodiment of the present invention, in which a motor drive device 2 is attached to a camera body 1, and a frame speed converter 3 is shown below.
shows. When using the frame speed converter 3, it can be attached to the motor drive device 2 by screwing the mounting screw 11 provided on the frame speed converter 3 into the tripod mounting screw 10 of the motor drive device 2. It is fixed to the bottom surface of 2.

An external signal connector 13 is provided on the front surface of the motor drive device 2, and when the frame speed converter 3 is attached to the motor drive device 2 with the mounting screws 11, the external signal connector 13 is provided opposite to the external signal connector 13. A first external signal connector 12 is provided at the position and connected thereto. Further, a second external signal connector 17 is provided on the front side of the frame speed converting device 3, that is, on the opposite side of the first external signal connector 12. This second external signal connector 17 is directly connected to the first external signal connector 12, and when the frame speed converter 3 is attached to the motor drive device 2 and the external signal connector 13 is used for the frame speed converter. It is connected to other accessories, and signals are exchanged between the other accessories and the motor drive device via the second external signal connector 17, the first external signal connector 12, and the external connector 13 of the motor drive device. This makes it possible.

A ring-shaped frame speed conversion dial 14 is further provided on the front surface of the frame speed conversion device 3, and a release button 15 for starting the motor drive device 2 is provided at the center of this dial. is in a position that is easy to operate when the camera is held vertically to take pictures. The release button 16 of the motor drive device 2 and the release button 15 of the frame speed conversion device 3 are
It is set to perform the same action no matter which button you press.

Figure 3 is an enlarged view of the frame speed conversion dial.As a specific example of the frame speed conversion shown in the figure, the characters "1", "2", and "3" on the dial 14 are indicators. 3a, it indicates that continuous shooting of 1 frame, 2 frames, and 3 frames per second can be performed, respectively, and the letter "M" indicates that only the release button of the frame speed converter 3 is pressed without performing frame speed conversion. This indicates the mode you want to use, and at this time, photography is performed at a frame speed determined by the motor drive device itself. The "OFF" indication is a position in which frame speed conversion is not performed and the release button 15 is mechanically locked when the release button 15 is not used. In the embodiment, three types of frame speeds can be set, but the frame speed conversion may be changed continuously.

FIG. 4 shows a circuit diagram of the above embodiment.

Blocks 1, 2, and 3 represent a camera body, a motor drive device, and a frame speed converter, respectively.

The camera body 1 includes a camera control circuit 4, and external terminals T ₁ , T ₂ , T ₃ , T ₄ of the camera body 1 are external terminals T′ ₁ , T′ 2 , T′ ₂ of the motor drive device 2, respectively.
Connected to T′ ₃ and T′ ₄ . Terminals T ₁ and T′ ₁ are grounded, respectively, and a shutter close signal indicating that the camera shutter has been closed is sent from the camera body to the motor drive device via terminals T ₂ and T′ ₂ . A release signal to release the camera shutter is sent from the motor drive device to the camera body via terminals T ₃ and T' ₃ , and a release signal to release the camera shutter is sent from the motor drive device to the camera body via terminals T ₄ and T' ₄ . A photometry start signal is sent to activate the photometry device in the main body. The closing signal is generated from the time when the shutter is closed until the time when the shutter charging and film winding are completed.

The motor drive device 2 includes a motor drive control circuit 5, a power supply 6, a motor 7, a transistor Q ₁ ,
Resistors R ₁ , R ₂ , R ₃ and photometry start switch SW ₁ ,
Consists of switch SW ₂ for shutter release. Switches SW ₁ and SW ₂ are linked to the release button 16 of the motor drive device 2, and when it is pushed down to the first stroke, switch SW ₁ is closed, and when it is pushed down further to the second stroke, switch SW ₂ is closed. Ru. The motor drive control circuit 5 is powered by a power source 6, and when switches SW ₁ and SW ₂ are closed, a photometry start signal and a release signal are sent to the camera body via terminals T' ₃ and T' ₄ , respectively. When the motor drive control circuit 5 receives a shutter close signal from the camera body via the terminal _T'2 , it generates a Lo (low) level signal at the terminal _P6 , which serves as a winding signal. The other external terminal group T ₅ to _{T 10} of the motor drive device 2
is housed in _the external connector ₁₃ shown in _FIG . Connected to terminal P ₆ , external terminal T ₈ receives a release inhibit signal from the outside,
It is sent to the terminal P ₇ of the control circuit 5. External terminal _T9 ,
_T10 is connected to switches _SW1 and _SW2 , respectively. It should be noted that while the control circuit 5 receives a Low level signal acting as a release prohibition signal at the terminal _P7 , the control circuit 5 prevents generation of a release signal from the terminal _P3 even though the release switch _SW2 is closed.

External terminals T' ₅ to T' ₁₀ of the frame speed converting device 3 are housed in the first external connector 12 shown in FIG. 1, and are connected to external terminals T ₅ to T ₁₀ of the motor drive device 2, respectively. This external terminal T' ₅ has five contacts a ₁ , b ₁ , c ₁ , d ₁ ,
e ₁ is connected to the movable contact piece of the first 5-contact switch SW, the external terminal T' ₆ is grounded, and the external terminal
T' ₇ is connected to the input of a first switching circuit consisting of resistors R ₄ , R ₅ and transistor Q ₂ and to the input of a second switching circuit consisting of resistors R ₆ , R ₇ and transistor Q ₃ , respectively. . Also external terminal
T' ₈ is connected to the collector of a transistor Q ₈ for generating a release prohibition signal, and external terminals T' ₉ and T' ₁₀ are connected to a photometry start switch SW ₃ and a shutter release switch SW ₄ , respectively. These switches SW ₃ and SW ₄ are connected in parallel with the switches SW ₁ and SW ₂ of the motor drive device via terminals T ₉ , T' ₉ , T ₁₀ and T' ₁₀ , respectively, and the release button of FIG. 15, the button is sequentially closed by pressing the button up to the first stroke and then down to the second stroke. The second 5-contact switch _SW'5
It has the same configuration as the five-contact switch SW ₅ , and consists of five contacts a ₂ , b ₂ , c ₂ , d ₂ , e ₂ and a movable contact piece.
These first and second 5-contact switches SW ₅ ,
SW' ₅ is linked to the dial 14 in FIG. 1, and the letters "1", "2", "3", "M",
When “OFF” corresponds to each index 3a,
The movable contact pieces have contacts a ₁ , a ₂ ; b ₁ , b ₂ ; c ₁ ,
Connected to c ₂ ; d ₁ , d ₂ ; e ₁ , e ₂ . This first 5
When the contact switch SW ₅ is connected to any one of the contacts a ₁ , b ₁ , and c ₁ , the contact switch SW 5 supplies power to various circuits in the frame speed converter 3 from the power source 6 of the motor drive device.
Resistors R ₈ , R ₉ , R ₁₀ , time integration capacitor C ₁ , and transistor Q ₄ constitute a timer circuit for the reference voltage circuit, and generate a timer output for a certain period of time from the time when the winding signal is generated. Resistors R ₁₁ , R ₁₂ , R ₁₃ , Zener diode ZD, and transistors Q ₅ and Q ₆ output a constant reference voltage Vcc 1 that is independent of voltage fluctuations of power supply 6 while the above timer output is being generated, and output a constant reference voltage Vcc ₁ to the emitter of transistor Q ₆ . Output to. Resistance R ₁₄ , R ₁₅ , R ₁₆ , capacitor
The differentiation circuit consisting of C ₂ is the first switching circuit.
The signals sent from R ₄ , R ₅ , and Q ₂ are differentiated, and the reset transistor Q ₇ is turned on instantly. This transistor Q ₇ and resistors R ₁₇ , R ₁₈ , R ₁₉ , R ₂₀ , R ₂₁ ,
R ₂₂ , R ₂₃ , time integration capacitor C ₃ , and comparator 8 constitute a frame speed determining timer circuit that determines the frame speed of the motor drive device. Resistance R ₁₇ ,
R ₁₈ and R ₁₉ are connected between contacts a ₂ , b ₂ , c ₂ and capacitor C ₃ , respectively, and control the charging current of capacitor C ₃ , and the resistance value is the maximum for resistor R ₁₇ ,
R ₁₉ is specified as a minimum. The resistances R ₂₀ and R ₂₁ are
This is a voltage dividing resistor that divides Vcc ₁ . Comparator 8 connects the charging voltage of capacitor C ₃ and voltage dividing resistor R ₂₀ ,
Compare the reference voltage Vcc ₁ divided by R ₂₁ ,
When the two have a predetermined relationship, the inhibit signal generating transistor _Q8 is turned on. this transistor
When _Q8 is turned on, it works as a release prohibition signal.
A Lo level signal is sent to external terminal _T'8 .

Although the six external terminals in the second external signal connector 17 of FIG. 1 are not shown in FIG. 4, these terminals are directly connected to T' ₅ to T' ₁₀ , respectively. There is.

Next, the operation of this embodiment will be explained.

(i) When the switches SW ₅ and SW' ₅ are selected as the contacts d ₁ and d ₂ , the power supply to the circuit in the frame speed converter 3 is cut off, so the transistor Q ₈ is always off.
Terminals T ₈ and T' ₈ are kept open, and the frame speed converter 3
The same sequence as when not attached to the motor drive device 2 operates as follows. A time chart at this time is shown in FIG.

When the release button 15 or 16 is pressed down, the photometry start switch _SW1 or _SW3 closes, and a photometry start signal is sent from the terminal P4 of the motor drive control circuit ₅ to control the camera body 1 via the terminals _T'4 : _T4 . circuit 4
is sent, and the camera body starts metering. If you press the release button further, release switch SW ₂
Alternatively, SW ₄ is closed, and a release signal is sent from terminal P ₃ of motor drive control circuit 5 to control circuit 4 of camera body 1 via terminals T ₃ ; T' ₃ to start shutter release. When the shutter trailing curtain closes after a predetermined shutter exposure time has elapsed, a shutter close signal is transmitted from the control circuit 4 to the motor drive control circuit 5 via the terminals _T2 ; _T'2 . Immediately after the shutter close signal is generated, the motor drive control circuit 5 generates a Lo level voltage as a winding signal at the terminal _P6 ,
Transistor _Q1 is turned on and motor 7 is energized. When the motor 7 rotates, the film in the camera body 1 is wound, and the shutter is charged, the shutter close signal disappears, the winding signal also disappears, and the voltage at terminal P ₆ returns to Hi level, ending the energization of the motor. do. If the shooting mode of the motor drive is continuous shooting mode and the release button is kept pressed down, the release signal whose sending was stopped during winding will be sent out again from terminal T'₃; T ₃ , and the above will occur. The sequence is repeated.

When the switches SW ₅ and SW' ₅ are connected to the contacts e ₁ and e ₂ , the release button 15 of the frame speed converter 3 is mechanically locked, so in this case, the release button 16 of the motor drive device can be used. becomes.

(ii) Switches SW ₅ and SW′ ₅ are connected to terminals a ₁ , a ₂ ; b ₁ ,
When either b ₂ ; c ₁ or c ₂ is selected, the time chart at this time is shown in Fig. 6. In the standby state, the terminal _P6 of the motor drive control circuit 5 is at Hi level, that is, the winding signal has disappeared and the capacitor _C1 is discharged, so the transistor _Q6 is off, and the transistor _Q8 is also off, and the terminal T′ ₈ ; T ₈
is open and no release prohibition signal is generated. In this state, when the release button 15 or 16 is pressed deeply, photometry and release are started in the same sequence as in the previous section (i). Camera body 1 after exposure
A shutter close signal is transmitted from the motor drive control circuit 5 to the terminal of the motor drive control circuit 5.
When the hoisting signal Lo is output from _P6 , the motor starts to be energized and is sent to the frame speed converter 3 via the terminals _T7 ; _T'7 . When the hoisting signal Lo is input, transistor Q ₃ is turned on, C ₁ is charged after a short delay by resistor R ₈ , transistors Q ₄ and Q ₅ are turned on, and the emitter of transistor Q ₆ is It is determined by the base-emitter voltage V _BE of the Zener diode and transistor _Q6 . A reference voltage Vcc ₁ independent of the power supply voltage is output.
The reference voltage Vcc ₁ is applied not only during the generation of the hoisting signal, but also
Even after it disappears, it remains connected for a timer period determined by capacitor C ₁ and resistors R ₉ and R ₁₀ . This timer time is set longer than the longest timer time for determining the frame speed determined by the capacitor C ₃ and any one of the resistors R ₁₇ , R ₁₈ , and R ₁₉ .

On the other hand, when the winding signal Lo occurs, the transistor Q ₂
is also turned on, and the differential pulse generated by capacitor C ₂ and resistors R ₁₄ , R ₁₅ , R ₁₆ momentarily turns on transistor Q ₇
is turned on, and if any charge is stored in capacitor _C3 , it is almost completely discharged. Immediately after transistor Q ₇ turns off, capacitor C ₃ connects to resistor R ₁₇ , which corresponds to the selected contact of switch SW′ ₅ .
The current from transistor Q ₆ flowing through R ₁₈ and R ₁₉ begins to charge. At this point, since the voltage at both input terminals of the comparator 8 is lower than that at the inverted input terminal, its output is at Hi level and the transistor _Q8 is on, generating a release prohibition signal. After the frame speed determination timer time set by the values of resistors R ₁₇ , R ₁₈ and R ₁₉ expires due to the increase in the charging voltage of capacitor C ₃ , the output of comparator 8 is inverted and transistor Q ₈ is turned off. In other words, the transistor _Q8 is turned on for one of three timer times immediately after the winding signal Lo is input, and generates a release prohibition signal, which causes the motor drive control circuit 5 to turn on the release switch SW even if the winding is finished. Even if _{SW 2} or SW ₄ is closed, the release signal is not sent from the motor drive control circuit 5 to the release control circuit 4. Timer time ends, transistor Q ₈
If the release switch is still closed when the shutter is turned off, a release signal is sent, the next release is started, and the sequence from release to winding is repeated.

As described above, the period during which the release prohibition signal is generated is determined by the time constant determined by the selected resistors R ₁₇ , R ₁₈ , R ₁₉ and capacitor C ₃ .
By selecting the resistance values of R ₁₇ , R ₁₈ , and R ₁₉ , when selecting resistors R ₁₇ , R ₁₈ , and R ₁₉ , the second
Continuous shooting of three frames is carried out.

When the shooting is finished, the reference voltage Vcc 1 disappears after the timer time determined by the capacitor C ₁ and resistors R ₉ and R ₁₀ from the time when the last winding signal disappears, and the reference voltage Vcc ₁ disappears and enters a standby state, and the frame speed conversion is started. Since the current consumption of the circuit of the device 3 becomes 0, wasteful power consumption can be avoided.

The frame speed of this continuous shooting is determined by the exposure time determined by the shutter speed and the exposure end time, that is, the release prohibition time from the start of winding to the start of the next release.The release prohibition time is determined by various factors such as the power supply voltage. Since it does not vary depending on conditions, a constant frame speed can always be obtained if the shutter time is negligible compared to the release inhibition time. however,
If the time required to wind the film exceeds the release prohibition time, the frame speed will naturally be slower than the predetermined frame speed.
The release prohibition time is set longer than the maximum value of the winding time.

As described above, the grounding, power output, and
By attaching it to the connection terminal that includes four signals: winding signal output and release prohibition signal input, the frame speed during continuous shooting can be changed to the highest speed by the motor drive unit alone, and by changing the mode with a switch. It is possible to select several types of fixed piece speeds that do not vary depending on other factors.

In the above-described embodiment, it is obvious that the film winding time from the closing of the shutter to the completion of winding is constant, provided that the power supply voltage does not change.

Further, in the embodiment described above, the external signal connector 13 connects the first external signal terminal 13, the external signal connector 12 connects the second external signal terminal, the dial 14 connects the operating member, the resistors _R17 to _R23 , and the comparator 8. Transistor Q ₇ and capacitor C ₃ constitute timer means, and transistor Q ₈ constitutes release inhibiting means.

As described above, according to the present invention, even if the motor drive device of the camera does not have a frame speed conversion function, the frame speed conversion can be operated using an external signal connector that may be generally provided. By preparing the device in a form that is detachable from the motor drive device, it is possible to make the motor drive device itself lightweight and to provide a rational system that can be used only by those who need it.

Further, even if there are various types of motor drive devices, if the same external signal connector is provided, one frame speed converter can be used for each motor drive device. Since it is separated from the motor drive device, additional functions such as the release button for vertical position can be installed without placing any burden on the motor drive device as long as the signal is output. can be expanded.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the appearance of a frame speed converter, a camera, and a motor drive device according to an embodiment of the present invention, and FIG.
The figure is a side view similar to Fig. 1, Fig. 3 is an enlarged view of a part of the frame speed converter of the embodiment, and Fig. 4 is the frame speed converter, camera, and motor drive of the embodiment. Figures 5 and 6 are time charts for explaining the operation of this embodiment. Explanation of symbols of main parts, frame speed conversion device...3,
Mounting screw...11, external connector...12,1
3,17.

Claims (1)

[Claims for Utility Model Registration] 1. A camera capable of repeatedly performing a shutter release operation and a winding operation, and capable of being attached to a motor drive device having an outwardly exposed first external signal terminal, A second external signal terminal that is connected to the first external signal terminal when attached to the motor drive device; an operating member that can be manually operated; and a control member that starts measuring time from a predetermined time and operates the operating member. a timer means for changing the time measurement in response to the timer means; and a timer means for prohibiting the shutter release operation of the camera at least from the completion of film winding until the time measurement is completed by the timer means based on the time measurement output of the timer means. A frame speed conversion device for a motor drive device of a camera, comprising a release inhibiting means for transmitting a signal to the second external signal terminal. 2. The timer means is provided to start timing in response to closing of the shutter, and the release inhibiting means is configured to control the timing from the time when the timer means starts timing until the timing is completed after film winding is completed. 2. The frame speed converting device according to claim 1, wherein a signal for inhibiting a shutter release operation is transmitted to the second external signal terminal during a period of time.