JPS62215252A - Film winding control circuit for camera - Google Patents

Abstract

PURPOSE:To make the reset time from the operation of a shutter button to the start of film winding constant regardless of variation in source voltage by comparing the charging voltage of a charging circuit which is charged after a shutter button is operated with a threshold voltage proportional to the source voltage and then winding a film. CONSTITUTION:When a switch 1 is turned off, a transistor (TR) X1 is turned off to charge a capacitor Cx through a current mirror circuit 13 and its charging voltage (e) rises with the time constant determined by a capacitor Cx and a resistance Rx provided outside an IC. The voltage (e) is applied to the negative input terminal of a comparator 10 and a voltage Vcc, on the other hand, is applied to the positive input terminal of the comparator 10, whose output (f) varies from an H level to an L level when said voltages becomes as high as each other. The output of a gate 14, therefore, rises to the H level to turn on TRs X2 and X3, and a current is supplied to a motor, which is driven to wind the film.

Description

[Detailed description of the invention]

Industrial Application Field The present invention relates to a film winding control circuit for a 35 mm camera, etc., and particularly relates to the time from the time the shutter button is operated to the start of film winding by the film winding motor (ret 1 to film winding interval). The present invention relates to a control circuit that can keep the voltage constant regardless of power supply voltage fluctuations. Conventional technology 35# Automatic film winding machine for cameras, etc. (-4
Conventionally, the film rolls after pressing the shirt button.
Rotate the motor 1! The old system automatically winds the film and detects that one frame of film has been run. -C
There is. FIG. 1 shows a circuit diagram of an example of a conventional camera monoluminescence winding control circuit. In the same figure, when the shirt button is pressed, the 91 door ivy switch 1 turns on automatically.

[After this, the film winding switch 2 turns on. As a result, the transistors Q+ and Q2 are turned on, and the film winding unit 3 is rotated by applying the voltage Vcc of the battery 4, and the film is wound up. The running of one frame of film is detected by a one-frame running detection circuit (not shown), and the switch 2 is turned A-F, 41-C7-93, or stopped. 'H, press the last frame of the film (・After pressing the vine button,
Similarly to the above case, the t-tater 3 rotates and the film winding 1-
However, in this case, even if the film is wound up, the film cannot be pulled out from the film case for more than a predetermined I'd. Therefore, the 1-frame running detection circuit cannot detect the 1-frame running and stop the energization to the motor 3.
4 (Fig. 2 (P)), the terminal voltage 11 of the terminal 11 (second terminal I) of (0)) reaches the constant ∆＠shipping power ff V s at lζ time t Io i
- Turn on transistor Q3, 1 to transistor Q+,
I set Q2 to J '7 G, ':, to stop the dryer 3. Figure 2 (4-)) accepts the period for energizing the t-tater 3. In this case, the time constant C2R2 is set to a value greater than 1F,', which is required for one frame of film tj. The transistor Q4 is for discharging the electric charge of the converter C2 at the same time as the shutter switch 1 is turned on so that the terminal voltage of the converter C2 starts from zero. In FIG. 4, the time constant circuit including the capacitor 01 and the resistor R1 is set at a value between 1 and 1.1. That is, after switch 2 is turned on, switch 1 is turned off 1),
]Nden', JC+ is ll:Il constant C+ due to voltage applied from power supply 4 and resistor R1.
R+ is charged, and this reaches a predetermined voltage.IL'+
Transistor Q5 is turned on, 1 to transistor Q6 is A, 1 to transistor Q1. When Q2 is turned on, the C motor 3 is energized and film winding is performed. Problems to be Solved by the Invention However, the reset time in the conventional circuit described above fluctuates in response to fluctuations in the power supply voltage.In other words, as the power supply voltage decreases, the reset time improves; There have been problems such as it takes a long time to wind up the film, making it difficult to perform continuous shooting, etc.The present invention provides a camera that can maintain a constant reset time regardless of fluctuations in power supply voltage and fluctuations in temperature. The purpose is to capture and provide a film winding control circuit.Means to solve the problem In Fig. 1, an operational amplifier 12, a current mirror circuit 13, -]nden→j'Cx, and a resistor Rx are connected to the After operation, the charging voltage is proportional to the charging voltage and the power supply voltage Vcc, which is proportional to the charging voltage and the power supply voltage Vcc.
. The charging voltage is compared to the threshold fIi if V (l -
M1] Voltage comparison means for detecting the signal, gate 14,]
The heshishin jitters X2, Xa, and the film winding motor 3 are embodiments of means for winding the film by detecting the voltage comparison means. Charging type 1 [e(
Characteristics f, IT, III in Figure 3) and threshold voltage Vo (Vo+, Vo2 in Figure 3) according to power supply voltage fluctuations
Compare O3) and ] comparator 101; and when the two match, perform film winding-1 and s[! tsu]·
The time t RS can be kept constant regardless of power supply voltage fluctuations and temperature fluctuations. Embodiment FIG. 1 shows a circuit diagram of an embodiment of the circuit of the present invention. In the figure, the same components as in FIG. When it is turned on (Fig. 2 (A)), the 1-run transistor Xl turns on,
At time t1, the film winding switch 2 is turned on ((C) in the same figure), and the voltage VIN and the power on/off drive circuit 11 are turned on.
The power supply voltage Vcc is applied to each element via
))become. When switch 1 turns off at time t2, transistor x1
is turned off, capacitor Cx is charged to Karen 1 via mirror circuit 13, and its charging voltage e (FIG. (IE)
) starts at time t2 with a time constant of IC91, (Sl, 1JC, and resistor Rx.) In this case, when the power supply voltage Vcc is applied, the resistors R+o, R+
The voltage divided by + is applied to the positive input terminal of the operational amplifier 12, and the output of the operational amplifier 12 is applied to the current mirror circuit 1.
3. The output current of the Karen miller mirror circuit 13 is the resistance R× and ]
The same value flows through the capacitor C×, and this current is equal to the power supply voltage Vc.
The voltage e also corresponds to fluctuations in the power supply voltage Vcc. Is the voltage e applied to the negative input terminal of the inverter 10? ,
> -/ノ, Den II' V (: (: k11n Rl
/ - ta 1 (1) +I input terminal -r to threshold vessel V (+ and [7 The output 1 of the T1 comparator 10 changes from 1 level to 1 level ((F) in the same figure).
The output of 4 becomes 1 level, l-transistor X2,
3 is turned on, +Yoke; 31. 11 current is supplied (-V-ta 3 turns Ii1 (the same figure (N)), and the node l
You can get 1-z/me. In this case, from time 12 the old M
t', 4 is between 1 and 4, and this length is l=
11 days ago, 11 days ago, 11 days ago, the words ``Yakii ζguchi'' will be sung. Note that the time from 11 to 4 is compared to the MSS stations described below. 1-Fungista×
4 is left at A-off: 1, the iF input terminal voltage TI- of the converter 2 is kept relatively high. Let us now consider the relationship between power supply voltage fluctuations and reset time. In Fig. 1, the negative input terminal pre-charge JT, e of one amparator 10 and the positive input terminal voltage of the amparator 10 (
Threshold IlO voltage Fl:) Vo is λ due to the fluctuation of the power source
For example, in Fig. 3, the broken line 1 and the solid line IF correspond to
, -r:, If the soragenden 1■- fluctuates to the dashed line 1■, =1 the threshold of the inverter 10 is the people's VOI, Vo2. Vo3 J, uni fluctuating Jru. Regardless of the fluctuations in these two people, J, Su, regardless of the fluctuations in the power supply light, Su! Is it constant for one hour (191, for example, 120m5)?
l le. In this case, rylene l-IC? The interval j r< S T is j
R8th = - 1---1 odor: 4-. −． ．． − −j−q−4g−
j-car-1! (ゞ 1< 8 ° R12
11, there are 3 ° l < 11 degrees. ] When the output r (Fig. 2 ([)) of the node 10 reaches the above-mentioned j, time 14- (river- level),
6 output) ((J) in the same figure) or 1 level and 41 = 1-transistor Now, at time 14, when output J■- of =1 inverter leak 10 becomes 1- level, inverter 15 (7) It
For the level output, J is 1 transistor x 1.
Ru. 0.53 V of 1 [two-person power Q11; Ryoden 111 (same figure (■))]
Then, the output of the comparator 18 k h'i l I
level and /r1), and at the same time as t-211, the output j of gate 16 ((J) in the figure) becomes level. - h, [- When the C film is wound by the rotation of the motor 3, the film feed hole moves -) (, pulse mirror 1
- The composition switch 6 is turned on, and the signal (] ((G) in the same figure) is taken out at the QE of A) Sane-Ci. ((11) in the same figure) and is supplied to the switching circuit 21 via the drive j circuit 20. its J(' i
@ Fig. 2 As shown in Figure (1), switch λ1, and now,
Buddhist gate i turns on transistor x 6 J: 11 level (Vcc), its A level (V) l-level (053V)
) Do<Eru. The output of the C-1 comparator 1B, which is the same as the signal 1 (1) If level and 1-level switching, is shown in Fig. 2 (
) <) Like 4 eternity. ] The output of the comparator 18 is =1, the output f of the comparator 10 is J, the output j of the rigs 1 to 16 is as shown in FIG. )' C) x is repeatedly charged and discharged until its p=:1
Electricity 11-. e is as shown in FIG. 2 (G). For frames without fI-) in the final frame, the charging/discharging operation is simply repeated like this (,7) during the Noilm winding. Ic 11; ￥Pass switch 2 will be automatically turned off and this charging will be stopped. <'t a3, 1 ndenri 0x charging/discharging is n, lr] The positive input terminal voltage C of the inverter 22 (FIG. 2 (1)) repeats up and down corresponding to the voltage e'? I. Here, at the final frame of C゛, 1I11, the film is pulled out from the film coop at time 17/, and at the time of 1I11 (
- The rotation of the printer 3 is stopped (1-), and the film is running, so the switch 6 is turned on, and there is no A-off, so the rotation is -1 (t x LJ It, ¥1).
．． The battery continues to be charged from [), and the voltage e continues to rise from 4 to +J. 17 pressure e is Yozuki - Setting circuit 17's 2 1 - No die A -
Threshold 111'l lightning set at ah- at Dz [f 1.
When it reaches 1/l V (time 18), the output port 1 of the node 22 ((M) in the same figure) is set to 1 level, and the output of 14 to 1/l V is 1 level. - level is returned, transistors X2 and X3 are turned off, and power supply to the motor 3 is stopped. At this time, the output m of the =1 inverter 22 is supplied to the latch circuit 234, and the transistor Xa
, In this case, film running will stop and I will stop! t6'l l
', the power supply from 7 to motor 3 is stopped and t=m interval 18
The motor 3 has been energized for the entire period up to 11.1 (Figure 2 (N> indicates the period 1111 when the motor 3 is energized), but the 1-cross period from time 17 to 1-8 is the time constant for MS time setting (j[
A (b shorter than the lifting platform of the circuit, and as a result, the time during which the tensile force is applied to the film is longer than that of the conventional circuit. Il
, '1 period is longer than the above-mentioned reset period 11 hours, and a relatively small 7MS lightning current (flowing in Cx) flows J.
Therefore, after time 14, the 1-heran jitter x 4 is turned on to make the positive input terminal voltage of the comparator 12 relatively low. Here, power supply voltage fluctuation and M S Il, ? Think about the relationship between spaces. In this embodiment, the Zener diode A-Dz of the voltage setting circuit 17 has a threshold voltage Vz of i, i4v that does not depend on the electric current mmllf, so as shown in FIG. When it fluctuates, the voltage e fluctuates as shown by the broken line 1, the solid line ■, and the dashed line ■, and the C threshold voltage Vz
(1,14V) By comparing, the MS time is ↑
MSI, tMs2, tMs3 of the power supply voltage (
It becomes longer in exactly inverse proportion to Il. Therefore, it is possible to reduce the error by Δ millimeter, which is inversely proportional to fluctuations in the power supply voltage, and to shorten the time during which the tensile force is applied to the film. Note that 1. between MS111. The voltage at the start of MS is 0.53 V, and is shown in FIG. In this case, the MS time Ms is: 1−-,,−,−,R,+4−−−1M S =Cx Rx ”R,,+1−<1.
'is. Here, VCES is power on A) Drive circuit 1
Saturation current F between the rector and the L-mitter of 1 transistor x 9
It is F. At time t8, the output b of the gate 25 (FIG. 2 (13)) switches to 1-level as the output m of the comparator 22 becomes the level for h, and as a result, the transistors XI2 and X+3 of the power supply A turn-off drive circuit 11 ．． X9 is turned off, and the supply of power supply Vcc (signal (j) (FIG. 2 (1))) is cut off. In addition, in this embodiment, the capacitor and resistor used to set the reset time 2 RST and the resistor used also serve as the capacitor and resistor that sets the MS time MS (-1 capacitor Cx and the resistor). R×), compared to the conventional circuit,
The number of parts for the mouth J can be reduced. Note that when the positive input terminal voltage of comparator 0 and the 0 input terminal voltage match and the output t becomes L level, 1
- The transistor X7 is turned on, and the voltage at the positive input terminal of the comparator 0 becomes low, thereby eliminating the chattering phenomenon of the output of the inverter 10, which corresponds to slight fluctuations in the power supply voltage. In FIG. 3, the voltage low width va is due to the power supply voltage fluctuation between 1 and transistor
This is the fluctuation range of the voltage at the positive input terminal of the comparator 8. According to the circuit of the present invention, after the shirt button is operated, the charging voltage of the charging circuit, which is charged according to the power supply voltage, is compared with a threshold voltage proportional to the power supply voltage, and the charging voltage is determined to be the threshold voltage. In order to detect a match and wind the film,
The time required for resetting 1 from when the shirt button is operated to when film winding starts can be kept constant regardless of power supply voltage fluctuations, and even when the power supply voltage drops, the time required to wind the film is shorter than that of conventional systems. 1, for example, if you are interested in the Oki Zoku Odori Kage, you will receive the special 1k of the customer.

[Brief explanation of drawings]

Figures 1 and 2 are the circuit diagram of the embodiment of the circuit of the present invention and its signal waveform diagram, and Figure 3 is the circuit diagram of the embodiment of the circuit of the present invention.
tFi TT fluctuation J, photoelectric voltage, time and MS 11. Figure 111 and Figure 4 are circuit diagrams of conventional circuits. l＼Volume 1.: u”shita, 4... Denshu (battery), 10...-1 amplifier,
12...A amplifier, 13...Power 1 non-1-mirror circuit, 11...Goo 1-117...Light setting circuit, O
×...IJINRI, 1<×. RIn・～・1ma12...Resistance, X+□～×3...
l-nonjista,.

Claims (1)

[Claims] A charging circuit that charges according to the power supply voltage after the shutter button is operated compares the charging voltage by the charging circuit with a threshold voltage proportional to the power supply voltage and detects that the charging voltage matches the threshold voltage. 1. A camera shutter winding control circuit comprising a voltage comparison circuit and a circuit that winds a film based on detection by the voltage comparison circuit.