JPH08254729A - Camera - Google Patents

Abstract

PURPOSE: To enable an electromagnetic driving source to be used as the load of battery check by energizing the coil of the electromagnetic driving source in a reverse direction to such an energizing direction that electromagnetic force for driving a light shielding member in order to execute an exposure action is generated, which is set as an energizing direction for the coil. CONSTITUTION: The yoke 24 and the permanent magnet 25 of the electromagnetic driving source are magnetized in the up-and-down direction. The movable coil 26 is pivotally supported so that it can be turned around a shaft P. By making a current flow to the coil 26, the electromagnetic force is generated and rotational force is generated. That means, the so-called meter type electromagnetic driving source is formed. In this way, the direction of the current flowing to the coil is reversed by detecting the ON-OFF of a contact point so as to be reciprocated. By energizing the coil of the electromagnetic driving source in the reverse direction to such an energizing direction that the electromagnetic force for driving the light shielding member in order to execute the exposure action is generated, which is set as the energizing direction for the coil, the battery check is executed. Thus, the battery check can be realized without using a lock member and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera of the type in which a light shielding member is driven by an electromagnetic force generated by energizing a coil to perform an exposure operation (opening / closing operation of a shutter).

[0002]

2. Description of the Related Art Conventionally, when checking a battery of a camera, a method of checking the battery by using an actual load of the camera (for example, a shutter starting electromagnet) has been adopted. In this case, since the current is supplied to the actual load, the load operates during the battery check operation (for example, a shutter starting electromagnet), and in order to prevent the shutter from actually traveling, the shutter member is prevented from traveling during the battery check. A method such as providing a stop member is employed.

[0003]

However, in the electromagnetically driven shutter of the type in which the light shielding member is directly driven by energizing the coil, the output shaft of the electromagnetic drive source is used as the drive shaft of the light shielding member, and the light shielding member is engaged. It will be difficult to take a stop configuration.

The object of the invention according to the present application is realized in a camera of the type in which a light-shielding member is driven by the electromagnetic drive source described above, with the electromagnetic drive source as an actual load and battery check without using the locking member or the like. It is intended to provide a camera that does.

[0005]

According to an aspect of the present invention, there is provided a camera provided with an electromagnetic drive source for driving a light shielding member by electromagnetic force to perform an exposure operation. The camera is characterized in that the battery is checked by energizing the light-shielding member in a direction opposite to an energizing direction for generating an electromagnetic force for driving the light-shielding member for an exposure operation.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 to 10 show a first embodiment of the present invention, and show an electromagnetically driven shutter of a camera which performs exposure on both forward and backward paths.

FIG. 1 is a perspective view showing the whole of this electromagnetically driven shutter (before the start of the forward travel or the completion of the backward travel), FIG. 2 is a front view of the shutter in the same state as FIG. 1, and FIG. 3 is FIG. 4 is a front view showing a state in which the electromagnetic drive source portion for controlling the operation of the shutter blade group is removed in the state of FIG. 4 (the blade drive lever, the brake mechanism, the signal contact piece, etc. are visible). In the front view showing the movement of the lever and the brake mechanism, the electromagnetic drive source portion is omitted. 4 shows the state immediately after the start of the slit exposure, FIG. 5 shows the same part of the latter half of the slit exposure, and FIG. 6 shows the fully open state. FIG. 7 is a front view of the shutter showing a state in which the outbound traveling is completed or before the inbound traveling is started. FIG. 8 is a front view showing the state of FIG.

In FIGS. 1 to 8, 1 is a shutter base plate, and an opening 1a is provided substantially in the center of the plane. Reference numeral 2 denotes a cover plate which is attached to the shutter base plate 1 so as to keep a constant gap, and has a similar opening (not shown) at a position corresponding to the opening 1a. A blade group 3 and a blade group 4 are provided between the shutter base plate 1 and the cover plate 2 with a partition plate 5 (having an opening 5a at a position corresponding to the opening 1a) interposed therebetween. Each of the two blade arms 6 and 7 (the blade arm of the blade group 3 is not shown) and a known link mechanism are operated to open and close the opening. Reference numeral 8 denotes a blade dowel for rotatably connecting the blade and the blade arm, and both blades have the same structure as the blade unit.

Here, regarding the drive of the blade group 3,
Since the components related to the driving of the blade group 4 perform almost the same structure and operation, hereinafter, the reference numerals of the components related to the driving of the blade group 4 are represented by numerals obtained by adding 100 to the reference numerals related to the driving of the blade group 3. , The driving of the blade group 3 will be described.

Reference numeral 9 denotes a drive lever, which includes a blade arm 6 and a pin 9.
a, and drives the blade group 3 to open and close by rotating about the axis P. The lever 9 has a hole 9b near the center of the lever 9 for receiving the transmission of driving force. The transmission-side pin (planted on the lower surface of the coupling lever 10 described later, (The same diameter as the provided pin 10c) and a predetermined play in the rotation direction about the axis P.

The connecting lever 10 is directly connected to the output shaft (coaxial with the shaft P) of the electromagnetic drive source, and the rotational force around the shaft P of the electromagnetic drive source is driven by the pin on the lower surface transmission side of the pin 10c. Arm having a spring property on the brake lever 11 due to the lower upright bent portions 10a and 10b (in FIG. 3, the spring property is in the direction of arrow A, and is hard to bend at a right angle to arrow A). The brake lever 1 is engaged with the parts 11a and 11b.
1 is rotated around the axis R in a predetermined direction and at a predetermined angle, and the blade group 3 is rotated.
Release the stopper at the start of running and generate the braking effect at the end of running.

In addition to the above-mentioned structure, the brake lever 11 acts on the side surface of the pin 9a of the drive lever 9 to provide the protrusions 11c and 11d serving as stoppers and brakes, and to provide a rotation behavior about the axis R. Arm 11e which receives the force of the spring 15
have. Reference numeral 12 denotes a stopper pin which abuts against the side surface of the brake lever 11 and restricts clockwise rotation of the lever 11, reference numeral 13 denotes a stopper pin which also restricts counterclockwise rotation of the brake lever 11, and reference numeral 14 denotes swing. A lever 15 pivotally supported about an axis T and supports a spring 15 at the tip of the lever to give the brake levers 11 and 111 rotation characteristics about the axis R and the axis S, respectively. The rotation about the axis T is performed by the balance of the spring force of No. 15.

Reference numerals 16 and 17 denote rubber stoppers which act on the side surfaces of the pins 9a of the drive lever 9 to reduce shock to the blades at the end of the travel of the blades. Reference numeral 18 denotes a base plate for an electromagnetic drive source, which is made of an insulating and non-magnetic material such as plastic and has an electromagnetic drive source for driving and controlling the blade group on the upper side and a signal connection for detecting the traveling state of the blade group on the lower side. The shutter base plate 1 is provided with screws 19 and 20 and 119 and 120 by means of screws 21.
Is fixed to a column 22 implanted in the slab. Here, the bases of the contact pieces 19 and 20 are supported by the base plate 18, and the positions of the contact pieces 19 and 20 are determined by abutment with pretension on the pins 23 implanted below the base plate 18. The position is in the rotation area around the axis P of the pin 10c, and the contact is turned ON-OF in response to the opening / closing operation of the blade group 3.
By performing F, the traveling state of the blade group is detected.

Reference numeral 24 denotes a yoke of an electromagnetic drive source, and 25 denotes a permanent magnet, which is magnetized in the vertical direction in the figure. Reference numeral 26 denotes a movable coil, which is rotatably supported around an axis P, generates an electromagnetic force by flowing an electric current, and forms a so-called meter-type electromagnetic drive source that generates a rotational force. Then, the direction of the current to the coil is reversed by detecting ON-OFF of the above-mentioned contact, so that the coil reciprocates. Two
Reference numeral 7 is a pressing plate for fixing the electromagnetic drive source to the base plate 18, and is connected to the base plate 18 with screws 28.

FIG. 9 is a block diagram showing an electrical configuration of this embodiment. In FIG. 9, PRS is a control circuit, for example, a CPU (central processing unit), RAM, RO
This is a one-chip microcomputer in which an M, an input port, a timer circuit, etc. are arranged, and software and parameters for shutter control and the like are stored in the ROM. The port performs input of a switch for detecting the state of the shutter, output of a shutter energization signal, and the like. The timer counts the set time and measures the time of shutter control. SHT is a shutter control circuit which energizes the electromagnetic drive sources MG1 and MG2 in response to control signals SSHT1 and SSHT2 from the control circuit PRS and a traveling direction signal SDIR, respectively.

When power is supplied to the electromagnetic drive source MG1, the blade group 3 travels in the direction specified by the traveling direction signal SDIR. After a lapse of time from the start of energization to the completion of traveling of the blade group 3, the energization is stopped. The same applies to feather group 4.
When the electromagnetic drive source MG2 is energized by two signals, the blade group 4 is driven.

The state of the shutter is transmitted from the shutter control circuit SHT to the control circuit PRS by state signals SSW1 and SSW2. SSW1 is "H" when the signal contacts 19 and 20 are conductive.
Is output, and SSW2 outputs "H" when the signal contacts 119 and 120 are conductive. At the time of each disconnection state, "L" is output. When SSW1 = “H” and SSW2 = “L”, it is before the start of forward traveling (FIG. 3), and conversely, SSW1 = “L” and SSW2 = “H”
In this case, before the start of the return travel (after the end of the forward travel) (FIG. 8). When the shutter is fully open (Fig. 6), SSW1 =
“L”, SSW2 = “L”.

Next, the operation of the embodiment thus configured will be described.

Referring to FIG. 1 to FIG. 3 as a start state of forward traveling, first, it is checked whether or not the battery has enough energy to operate the camera correctly, that is, a so-called battery check is performed. At this time, the coils 26 and 126 of the electromagnetic drive sources for controlling the driving of the blade group 3 and the blade group 4, respectively, are rotated counterclockwise around the rotation axes P and Q, that is, the directions in which the blades travel from now on and the exposure is performed. A predetermined current is supplied for a predetermined time so as to apply a rotational force in the opposite direction (lock direction).

In this case, a state in which both coils are energized at the same time at high speed (the power supply condition is the strictest) is reproduced by performing a battery check by energizing both coils at the same time. Is guaranteed, and furthermore, a disconnection check of both coils is performed. However, the battery can be checked even if only one of the coils is energized. If battery check N
If G (No), the camera stops the sequence and becomes inactive. If the battery check indicates OK (good), the coil 26 of the electromagnetic drive source for controlling the driving of the blade group 3 (which becomes the leading blade when traveling forward) causes the coil 26 to rotate clockwise around the axis P. , And a shutter starts an exposure operation. The rotation of the coil 26 is transmitted to the connecting lever 10 as it is, and the lever starts to rotate clockwise around the axis P.

At this time, the pin on the lower surface of the connecting lever 10 and the hole 9b of the driving lever 9 have play on the clockwise turning side as shown in FIG. The blade group 3 is still in the start preparation position. Further, the brake lever 11
The lever 15 is brought into contact with the stopper pin 12 with the side face of the lever being kept clockwise about the axis R by the spring 15 and the projection 11c is moved by a predetermined amount within the travel area of the pin 9a of the drive lever 9. Projecting, protrusion 11c and rubber stopper 1
7, the pin 9a of the drive lever 9 is pressed in the area formed by the blade 7 to regulate the fluctuation of the start preparation position of the blade group 3.

Immediately after the rotation of the connecting lever 10, the lever 10
Of the brake lever 11
Is pushed in a direction substantially perpendicular to the direction of arrow A, and the brake lever 11 is rotated counterclockwise around the axis R against the clockwise rotation behavior of the spring 15. And
The rotation of the connecting lever 10 eliminates the play between the pin on the lower surface and the hole 9b of the drive lever 9, and at the time of contact, the brake lever 11 retreats its protruding portion 11c out of the travel area of the pin 9a. Has been turned up. Here, for the first time, the rotational force of the electromagnetic drive source is transmitted to the drive lever 9, the drive lever 9 starts rotating clockwise around the axis P, and the blade group 3 starts the opening operation. At this time, since the connecting lever 10 makes a certain amount of rotational angle run-up to give momentum, the rising edge of the opening operation of the blade group 3 becomes sharp, which contributes to the improvement of the curtain speed.

Shortly after, as shown in FIG. 4, immediately after the blade group 3 starts opening, the connecting lever 10 further rotates the brake lever 11 counterclockwise, and the lower standing bent portion 10a and the arm portion are turned.
Release the engagement with 11a. At this time, the brake lever 11 has already been given a rotation behavior about the axis R in the counterclockwise direction. This is because the swing lever 14 rotates clockwise around the axis T to a position where the spring 15 can be balanced by the positions of the arms 11e and 111e of the brake levers 11 and 111.

After the energization of the coil 26 for the blade group 3 is started, a predetermined exposure time T is set so that proper exposure can be performed.
[Second time according to the number of exposure steps of the camera, for example, 1/2 ⁿ
(N is an integer) seconds] and after adding a time ΔT1 (so-called gettering) which must be adjusted according to the response characteristics and driveability of the drive control system specific to the shutter unit or the running characteristics of the blade system. Then, energization of the coil 126 for the blade group 4 is started, and the closing operation is performed.

Further, after a lapse of time, as shown in FIG.
Immediately before the blade group 3 finishes traveling, the brake lever 11
With the counterclockwise rotation behavior of the spring 15 already in place, the side surface of the lever is brought into contact with the stopper pin 13 so that the projection 11d projects a predetermined amount into the travel area of the pin 9a of the drive lever 9. Waits for the pin 9a to run.

When the pin 9a comes into contact with the projection 11d, the traveling energy of the blade group 3 is considerable, and the pin 9a
Turns the brake lever 11 clockwise against the counterclockwise rotation behavior of the spring 15 of the brake lever 11 and attempts to shift to the final stop position.

At the same time, the lower bent portion 10 of the connecting lever 10
b contacts the side surface of the arm portion 11b having the spring property of the brake lever 11, pushes the arm portion 11b in the direction of arrow A, and also tries to move to the final stop position. Therefore, the blade group 3 is braked by the conversion of the energy into the spring reaction and the rotational movement by the brake lever 11, and the stable running with excellent durability becomes possible. Further, immediately after the blade group 3 reaches the travel completion position, the projection 11 d of the brake lever 11, which is provided with the rotation behavior in the counterclockwise direction by the spring 15, pushes the pin 9 a to the rubber stopper 1.
6 is pressed down to the area side formed and removed. The signal contact pieces 19 and 20 that were in the contact (ON) state before the blade group 3 traveled (FIG. 3) are
At the time of completion of running (Figs. 6 and 8), no contact (OFF)
It becomes a state.

Blade group 4 (rear blade during forward traveling)
Performs exactly the same operation as that of the blade group 3 with respect to its driving and braking except that the closing operation is performed.
And before the blade group 4 runs (FIGS. 3 and 6),
The signal contact pieces 119 and 120 that have been in the non-contact (OFF) state are in the contact (ON) state at the time when the traveling of the blade group 4 is completed (FIG. 8).

The above-described brake mechanism can operate in the same manner as described above regardless of the case of the slit exposure shown in FIG. 5 or the case of the fully open exposure shown in FIG.

As shown in FIGS. 7 and 8, the outward traveling is completed, the blade group 4 closes the opening, and the exposure is completed. In this state, those involved in the blade group 3 and those involved in the blade group 4 are completely reversed as compared to before the start of the outward traveling. In other words, this state is the next homeward traveling start state. Therefore,
The control microcomputer of the camera uses the contact pieces 19, 20 and
The drive control of each of the blade groups 3, 4 is performed so that the ON and OFF states of 119, 120 are reversed from before the start of the forward travel, and the traveling directions of the blade groups 3, 4 are opposite to those during the forward travel. The direction of energization to the coils 26 and 126 is reversed.

Hereinafter, the operation of each part of the backward traveling is reversed from that of the forward traveling (for example, the projection 11d of the brake lever 11 regulates the fluctuation of the start preparation position of the blade group 3 and the projection 11c is controlled by the blade 11c). At the end of the running of the group 3, the functions of braking and preventing bouncing are performed.) Since similar operations are performed, only the characteristic portions will be described.

First, regarding the battery check, each coil is energized so that a rotational force is applied in the direction (locking direction) opposite to the direction in which exposure is performed in the return trip.

On the other hand, the only difference from the forward traveling is the geta tone, in which the roles of the leading blade and the trailing blade are alternated in the blade group 3 and the blade group 4, so that the order of energizing the coils of the respective electromagnetic drive sources is changed. Due to the subtle difference in the characteristics of the two electromagnetic drive sources, the difference in the characteristics of the same electromagnetic drive source itself due to the difference in the rotation direction, the difference in the blade group operating load due to the difference in the blade group traveling direction, etc. Since proper exposure time accuracy cannot be obtained with the getter tone ΔT1 during traveling, another getter tone ΔT2 is provided for returning travel, and the signal contact pieces 19, 20 and
Detects ON / OFF status of 119,120 and switches.

When the return trip is completed, the state shown in FIG. 3 is reached, and the contact pieces 19, 20 and 119, 120 are turned on,
Since the OFF state is reversed from before the start of the backward travel (that is, the same as before the start of the forward travel), the control microcomputer of the camera detects this, and reverses the direction of energization to the coils 26 and 126 again. Is switched to .DELTA.T1 to enter the forward traveling state described at the beginning of the operation description.

Next, the electromagnetic shutter drive will be described with reference to the timing chart of FIG.

(Time a): The battery is checked by simultaneously energizing SSHT1 and SSHT2. The state of the shutters is after the completion of the backward traveling, so the shutter blade group 3 is closed and the shutter blade group 4 is open.

Therefore, SSW1 = "H" and SSW2 = "L". In the battery check, power is supplied in the direction in which the shutter blades do not travel, that is, the blade group 3 is opened and closed, and the blade group 4 is closed and opened. Such an energizing direction is designated by SDIR = “H”.

(Time b): When the battery check is completed, SDIR is set to "L" to change the running direction of the shutter. Thus, the shutter traveling direction on the outward path is set.

(Time c): When the electromagnetic drive source of the shutter blade group 3 is energized, the shutter blade group 3 travels from the closing direction to the opening direction and becomes the front curtain.

(Time d): When the shutter blade group 3 is opened, SSW1 = "L".

(Time e): The energization of SSHT1 is stopped after a sufficient time has elapsed for the shutter blades to travel from time c.

(Time f): A predetermined exposure time T from time c
After the time obtained by adding と T1 to ゲ T1, SSHT2 = “H”, and the shutter blade group 4 runs. The shutter blade group 4
When SDIR = “L”, power is supplied from the opening to the closing direction (rear curtain running).

(Time g): When the shutter blade group 4 is not in the open state, SSW2 becomes "H".

(Time h): The energization of SSHT2 is stopped after a certain time has passed from the time f.

In this way, the outward travel of the shutter is completed. At this time, the shutter blade group 3 is opened, the shutter blade group 4 is closed, and in the traveling direction SDIR = “L”, the blade group 3
Is closed → open, and blade group 4 remains open → closed.

Next, a description will be given of traveling on the return route.

(Time i): A battery check is performed. Since the traveling direction is the same as that at time h, traveling is not performed. The battery is checked at time a and the power is supplied in the reverse direction.

(Time j): After battery check, SDIR
= "H" to set the running direction in reverse.

(Time k): On the return path, the shutter blade 4 serves as the front curtain and travels first.

(Time l): When the shutter blade group 4 is opened, SSW2 becomes "L".

(Time m): After a certain period of time from time k, SSHT2 stops energization.

(Time n): a predetermined exposure time T from time k
Then, after a time obtained by adding another getter tone ΔT2 to the time of the forward trip, the running of the shutter blade group 3 is started (SSHT1 = “H”).

(Time o): When the shutter blade group 3 is not in the open state, SSW1 = "H".

(Time p): After a predetermined time has elapsed from time n, SSHT1 is set to "L" and the energization is terminated.

In this manner, the backward travel of the shutter is completed.

[0056]

According to the present invention, when the battery is checked, a current is supplied to the coil of the electromagnetic drive source in a direction opposite to the current supply direction for generating the electromagnetic force to be driven for the light shielding member exposure operation. By performing the battery check, the electromagnetic drive source can be used as an actual load of the battery check without providing a locking member.

[Brief description of drawings]

FIG. 1 is an exemplary perspective view showing an entire electromagnetically driven shutter of a camera according to a first embodiment of the present invention;

FIG. 2 is a front view of FIG. 1;

FIG. 3 is a front view showing a state where an electromagnetic drive source portion is removed in the state of FIG. 2;

FIG. 4 is a front view showing the movement of a blade drive lever and a brake mechanism immediately after the start of slit exposure according to the first embodiment.

FIG. 5 is a front view showing the movements of the blade drive lever and the brake mechanism during the latter half of the slit exposure of the first embodiment.

FIG. 6 is a front view showing the movements of a blade drive lever and a brake mechanism for full-open exposure according to the first embodiment.

FIG. 7 is a front view of the shutter showing the state before the completion of the outward travel or the start of the backward travel according to the first embodiment.

FIG. 8 is a front view showing a state in which an electromagnetic drive source portion is removed in the state of FIG. 7;

FIG. 9 is a block diagram of an electrical configuration of the first embodiment.

FIG. 10 is a timing chart of the electrical configuration of the first embodiment.

[Explanation of symbols]

 1 ... Shutter base plate, 2 ... Cover plate, 3,4 ... Blade group, 6,7 ... Blade arm, 8 ... Blade dowel, 9,109 ... Drive lever, 10,110 ... Connecting lever, 11,111 ... Brake lever, 14 ... Swing lever, 15… Spring, 16,17,116,117… Rubber stopper, 18… Electromagnetic drive source ground plate, 19,20,119,120… Signal contact piece, 24,124… Yoke 25,125… Permanent magnet, 26,126… Moveable coil 27,127… Pressing plate.

Claims (1)

[Claims] 1. A camera provided with an electromagnetic drive source for driving a light-shielding member with an electromagnetic force to perform an exposure operation, wherein the light-shielding member is used for the exposure operation as an energizing direction for a coil of the electromagnetic drive source. The camera is characterized in that the battery is checked by energizing it in a direction opposite to the energizing direction in which the electromagnetic force for driving is generated.