JPS6323550A - Dc motor - Google Patents

Abstract

PURPOSE:To simplify the construction of a DC motor and to facilitate the manufacture of the motor by guiding leads for supplying power to first and second armature windings from either end of a casing into the casing. CONSTITUTION:A DC motor body is enclosed by a cylinder 2, and a casing made of an upper cover 4 and a lower cover 6. Permanent magnets 8a, 8b are fixed to the inner wall of the cylinder 2 to form a field. Winding elements R1a-R1c-R2a-R2c of first and second armature windings are wound on the arms 10a-10c of the core 10 supported to a rotational shaft 12. Brushes B1a, B1b and B2a, B2b for energizing the first and second windings are fixed to the covers 4, 6, respectively. The leads for energizing the motor are all led from the cover 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a DC motor used for winding and rewinding film in a camera.

[Prior Art] Conventionally, various DC motors that are driven by being supplied with voltage from a power source battery are known. However, in such a DC motor, if the voltage of the power supply battery decreases, the operation of the mechanism driven by the DC motor may become slow or the mechanism may stop operating.

Therefore, in order to use the driving force of the motor as effectively as possible, for example, in JP-A-60-194433, two types of gear trains are provided as a transmission mechanism for transmitting the rotation of the motor to the drive mechanism. A device has been proposed in which the motor is temporarily reversed when the rotational speed of the motor decreases to switch from the normal large torque gear train to the small torque gear train, so that the drive mechanism can be driven even at low speeds.

[Problems to be Solved by the Invention] However, in such a conventional device, in order to drive the DC motor even at low speed, two gear trains are required as a transmission mechanism. A switching mechanism for selectively using the power of the two gear trains is also required, which complicates the mechanical configuration, resulting in a large and expensive device.

Therefore, an object of the present invention is to simplify the configuration of equipment using such a DC motor by improving a method for drawing out lead wires in a DC motor, which allows effective use of the motor's driving force. At the same time, the aim is to make manufacturing easier.

[Means for solving the problem] In a DC motor including a magnetic field and an armature including two wound sets of armature windings and a commutator, both ends of the rotating shaft of the armature pass through each other. A casing having a pair of end faces is provided, and electric wires for supplying power to the first and second armature windings are introduced into the casing of the DC motor from either one of these end faces.

As the armature winding of this DC motor, a first armature winding is wound near the axis of the radial arm of the armature core of the armature, and a second armature winding is wound outside of the first armature winding. can do.

Further, a first commutator connected to the first armature winding and a second commutator connected to the second armature winding are arranged on one side of the rotation axis of the armature, It is also possible to introduce electric wires for supplying power to the first and second brushes, which are in contact with the commutators, respectively, into the casing of the DC motor from the end faces adjacent to the brushes.

Furthermore, a first commutator connected to the first armature winding and a second commutator connected to the second armature winding are arranged opposite to each other across the armature of the rotating shaft of the armature. Place it on the side of
A first commutator contacting these first and second commutators, respectively.
It is also possible to introduce an electric wire for supplying power to the second plan into the casing of the DC motor from one end face.

[Function] According to the present invention, current is supplied to the first and second armature windings when high-torque driving force is required even at low speeds, and current is supplied to the first and second armature windings when high-torque driving force is required even at low speeds. When driving force is required, the wiring can be optimally wired for a DC motor that switches to supply current only to the first or second armature winding.

[Example] Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 is a circuit diagram showing the concept of a DC motor to which the present invention is directed. In FIG. 1, R1 indicates a first armature winding wound around an iron core, which will be described later, and R2 indicates a second armature winding. The first armature winding R0 has a first terminal T1 and a second terminal T2, respectively, while the second armature winding R2 has a third terminal T3 and a fourth terminal T4. Each has its own. Here, the second terminal T2 and the third terminal T3 are connected to each other, and a single common terminal T
It is treated as 23. M indicates the entire motor.

2 is a DC power supply, one output terminal of which is connected to the fourth terminal T4, and the other output terminal connected to a switch Sw serving as a switching means. Switch Sw
can be selectively connected to the contact t1 connected to the first terminal T1 and the contact t2 connected to the common terminal T23. Therefore, in the first state where the switch Sw is connected to the contact t, voltage is supplied to the first terminal T and the fourth terminal T4, and in the second state where the switch SW is connected to the contact t2, voltage is supplied to the first terminal T and the fourth terminal T4. Common terminal T23 and fourth terminal 1゛4
Voltage is supplied to both.

Here, to explain about the DC motor, V − (R + r ) T + K 1 ΦN =・(],
) T- to 2ΦI -T, -(2)
It is known that this holds true. However, here, ■ is the voltage of the DC current #V, T is the torque generated by the motor M, r is the internal resistance of the DC current #V, R is the internal resistance of the motor M, N is the rotation speed of the motor M, and the inside is fixed. The child magnetic flux, To is the no-load torque, ■ is the current flowing through the motor M, and K1 and K2 are proportional constants determined according to the number of turns of the armature winding.

In addition, no-load torque T. is the torque caused by the bearing loss of the motor M, so even if T=O, I≠O.

Here, power supply voltage V, internal resistance r of power supply, stator magnetic flux Φ
, and no-load torque T. is constant, and the internal resistances of the first and second armature windings R- and R2 are R, R2, respectively. If the switch Sw in Fig. 1 is switched to the contact t2 side, then R= R2, and considering the starting torque Tα in this state, N=O, so V= (R2+ r ) I α −(3)Tα−(K
2) αΦI a (o ・・(4−), therefore, ■ ]′α−(K2) αΦ・□ To ・・(5) R2+
Here, ■α and (K2)α each represent a value of 2 for the current flowing through the motor M and the proportionality constant when the switch Sw is switched to the contact t2.

Also, T--T. Considering the rotational speed Nα at this time, since it is I-0, V= (K,) αΦNa − (6)
Therefore, ①Nα−...(7) (K1)αΦ is obtained.

Based on Tα and Nα determined by equations (5) and (7), a characteristic line (T -N) Can draw α.

Next, consider a state in which the switch Sw is switched to be connected to the contact t1. In this case, R
=R++R2, and the starting torque Tβ and rotational speed Nβ of the motor M are determined.

Using the same procedure as before and setting N=0, V-(R1+R2+7-) Iβ-(8)T
Since β-(K2)βΦ1β-T o -(9), X! becomes. However, here, ■β and (K2)β each represent a value of 2 for the current flowing through the motor M and the proportionality constant when the switch Sw is switched to the contact point t1.

Here, assuming that the two armature windings R1 and R2 have the same wire diameter, the proportionality constants 1 and 2 are proportional to their resistance values. Therefore, 1 times 2, and we get . Also, T--T. Then, since I=0, it becomes ~l. Here, the switch Sw is the contact 1. Since the value of 1 in the proportionality constant (K1)β in the state connected to the motor M is also proportional to the number of turns of the armature winding of the motor M, it becomes From the Q2) formula, ~l, therefore, Tβ>Tα 94.0η.

Furthermore, from equations (7) and 05)...08) is obtained, and therefore Nα>Nβ...09).

Here, from the equation Q6) and (Ill), as shown in FIG. 2, for the characteristic line (T-N) α when R=R2, the characteristic line (T- N) Be able to draw β. Then, the characteristic line (T-N) α and the characteristic line (T-N) β cross each other.

Note that R=R2 and R−R+ + shown in FIG.
How to draw the characteristic lines (T-■)α and (1'-1)β that show the relationship between current and torque in each state of R2 is based on the respective starting torques Tα and Tβ and the current value at the time of startup. Since α and Iβ are known, their coordinates (T
=T'α11-Iα) and (T=Tβ, I-1β) and the coordinates (T--T., N=0) may be connected with straight lines.

Hereinafter, specific examples of the DC motor according to the present invention will be explained.
This will be explained in detail with reference to the drawings.

(2) First Embodiment FIG. 3 is an exploded perspective view showing the structure of a main body of a two-pole, three-slot DC motor according to a first embodiment of the present invention.

The motor body is surrounded by a casing consisting of a cylinder 2, an upper lid 4, and a lower lid 6. The inner wall of the cylinder 2 has a substantially arcuate shape, and the inner wall of the cylinder 2 has a substantially arcuate shape. A pair of magnetized permanent magnets 3a, 3b
is fixed symmetrically with respect to the motor rotation axis X by means such as a mounting plate, and constitutes the field of this motor.

Reference numeral 10 denotes an electric machine fixed to a rotating shaft 12 supported by shaft holes 4c and 6c provided in the upper lid 4 and the lower lid 6 so as to be rotatable around the motor rotation axis X. This core 10 is rotationally symmetrical about the rotation axis
Three arms 10a, ], Ob, 1 with an interval of 20°
0c and a hole 10 (l) into which the rotating shaft 12 is fitted.As shown in FIG. 1st 1, 4 Winding elements R, a, R+b+ R of armature winding R1
+c and the winding elements R2a, R of the second armature winding R2
2b and R2C are wound in parallel in the radial direction from the motor rotation axis X.

On the other hand, a pair of brushes B la + Blb for feeding power to the first armature winding R1 are respectively fixed to the upper lid 4, and a second armature winding R is fixed to the lower lid 6.
A pair of brushes B28°B2b for supplying power to the brushes B28 and B2b are respectively fixed. Here, in order to attach the brush to the lower lid body 6, a pair of grooves 5a are provided inside the lower lid body 6.
5b are formed, and the ends of the brushes B2a+B2b can be fixed to these grooves 5a and 5b by press-fitting or the like, respectively. In addition, a brush B is also provided on the upper lid body 4.
+ a + B + b As shown in the front view of the inside of the upper lid body 4 in FIG. The end portions of the brushes B la + F 31b are respectively fixed to the brushes 4b by press-fitting or the like.

14 is configured to be able to contact the brushes B 2 a + B 2 b held on the lower lid body 4 as described above.
A commutator portion rotates integrally with the armature core 10, and the commutator portion 14 has a hole 14a through which the motor shaft 12 is fixedly fixed, and an insulating portion 14b.
Three commutators 52abl 52bc +S2ca that are rotationally symmetrical with respect to the motor rotation axis X are provided at the outermost periphery thereof, respectively.

16 is a brush Bla+ held on the upper lid body 4;
This commutator part 16 rotates integrally with the armature core 10 so as to be able to contact the Bib, and like the commutator part 14, this commutator part 16 also has a hole 16a through which the motor shaft 12 passes. and an insulating part 16b are formed, and three commutators 5lab+5lbc+5lca rotationally symmetrical with respect to the motor rotation axis X are provided on the outermost periphery thereof.

Here, the three commutators 5lab+5lb of the commutator section 16
The positional relationship between c+s+ca and the pair of brushes B lfi+ Bib is as shown in FIG. 4, and the three electrode parts 52ab and 52bc of the electrode 14
+52ca and a pair of plans 82a, B21,
The positional relationship with G is also the same as in Fig. 4.

Returning to FIG. 3, ], 8.20 are commutator parts 1.
4.1.6 and the armature core 10, and this spacer 18.20 is for securing space for winding the armature winding around the core 10 in the rotation axis direction. . Therefore, the motor shaft 12 includes, in order from the bottom of the figure, a commutator section 14, a spacer 18, an armature core 10,
The spacer 20 and the commutator section 16 are each integrated by a press-fit tube method, and together with the motor shaft 12, they constitute an armature.

FIG. 6 shows a vertical cross-sectional view taken along the Y-A-B-C)-C-D-Y line in FIG. 5 cited earlier.
It is also the same as the longitudinal sectional view taken along line 2-0-2 in the figure.

Further, a perspective view of the motor body in this embodiment is shown in FIG. 7, and as is clear from FIGS. 6 and 7, in this embodiment, the lead wires L1. L2
, all three L3 are pulled out from the upper lid body 4. Therefore, in order to wire the power supply to the pair of brushes 82a+B and b, which are installed in the lower lid 6, as shown in FIG. Two put spaces DS, DS2 surrounded by field permanent magnets 3a and 3b are utilized, and straight wires L2/ and L3, which will be described later, are passed through them, respectively.

Next, the electrical connection relationship of this embodiment will be explained. Returning to FIG. 3, winding element R1a of first armature winding R1
+ R1tz' RIC is connected to a pair of terminals La+ j! la, f2 lb+ 1! , lbs.
b lc+k 1m respectively, while winding elements R2a, R2b of the second armature winding R2
, R2C are a pair of downwardly drawn terminals A2. , A2a, f 2bl spear 26, β2c+
Each has β2o.

The schematic diagram of FIG. 8 shows a pair of terminals βla+ of the winding element R1a of the first armature winding R4.
jl! , , are connected at one end to the electrode S1a++ and at the other end to the electrode S lea . Furthermore, a pair of terminals β15゜l of the winding element Rib of the first armature winding R0
, 5 has one electrode S jab and the other electrode S lbc
are connected to each. Also, the first armature winding R
, a pair of terminals LC+ f! of winding element R1c. , I.C.
are connected at one end to the electrode S lbc and at the other end to the electrode S IcA .

On the other hand, the pair of terminals β2a+ 128 of the winding element R2a of the second armature winding R2 has one terminal connected to the electrode S28. and the other is connected to the electrode S 2ca . Furthermore, a pair of terminals of winding element R2b of second armature winding R2! 2
b, β2b, one of which is connected to the electrode S26. and the other one is S2b. are connected to each. Also, the second armature winding R2
A pair of terminals f! of winding element R2C of ! , 2 c + β
2o, one side is the electrode S2b. and the other is connected to the electrode S2ca, respectively.

Furthermore, the brush Bla fixed to the upper lid 4 passes through the aforementioned put space DS shown in FIG.
electrically connected to b.

Further, a lead wire L1 extending outside the motor body is electrically connected to the brush Blb fixed to the upper lid 4, while a brush B2a fixed to the lower lid 6 is electrically connected to the brush Blb as shown in FIG. A lead wire L3 extending outside through the illustrated dead space DS2 is electrically connected. and,
The tips of these lead wires L1, L2, and L3 are respectively connected to the terminals T1. This corresponds to T21 T4.

Second Embodiment In the first embodiment described above, the winding elements R+ a + Rlb, R+ c of the first armature winding R4 and the winding elements R2a+ R2b+ of the second armature winding R2.
R2O refers to the three arm portions 10a, 1 of the armature core 10.
0b and 10C so as to be lined up in the radial direction from the motor rotation axis X.
In the second embodiment shown in the longitudinal sectional view of the figure, the winding elements Rla, Rib, Rlc of the first armature winding R1 are connected to each arm 1. Winding requirements of the second armature winding R2 wound around Oa, 10b, 10c RLa, R2b, R2c
” It is wrapped in two layers.

Other configurations, functions, etc. are the same as those in the first embodiment, so detailed explanation thereof will be omitted.

3rd Embodiment The vertical cross-sectional view of FIG. 11 and its Δ-Δ(A'-A')
In the third embodiment shown in FIG. 12, which is a line sectional view, the armature core or its arm portion 10a, Job, 1
0c is divided into two in the direction parallel to the motor rotation axis 12, and winding elements R+ a, R+ b + R of the first armature winding R1 are formed in the arms of the first stage iron core.
+c, and the second armature winding R2 is attached to the arm of the second stage.
An armature including two sets of armature windings is constructed by winding the winding elements R2a, R2b, and R2c, respectively.

Note that 18, 20, and 22 in FIG. 11 are spacers, and the spacers 22 are provided to separate the armature cores because the armature core is divided in this embodiment.

Fourth Embodiment In the fourth embodiment shown in FIG. 13, two commutators 14.1
6 and two pairs of brushes B, , B, , B2. , B2b and B2b are arranged in parallel on the upper side of the armature 10 in the figure, and in order to avoid these commutators 14 and 16 from coming into contact with each other,
A space 1124 is placed between these commutators.

Further, winding elements R1a, Rlb, Rlc of the first armature winding R1 arranged closer to the rotating shaft 12
As shown in FIG. 14, which shows a cross section taken along line B-B in FIG. It penetrates through 26a, 26b, and 26c and is connected to the electrode 14.

In this embodiment, lead wires can be drawn out from each of the two pairs of brushes Bla, Blb, B2a, and B2b arranged above to form four input terminals as will be explained later with reference to FIG. possible.

In this embodiment, a bottomed cylindrical body 2 is provided with a hole 2b in the bottom surface 2a through which the rotary shaft 12 of the armature is inserted, and the brush B + covers the opening of the soil surface of the bottomed cylindrical body 2. a
, B + b + B 2 h , B 2
A casing is constituted by a holding part that holds the fixed end of b and a lid body 4 having a hole 4° through which the other side of the rotating shaft 12 is inserted. 8 is fixed by, for example, adhesive, a structure including an armature and a commutator is inserted through the opening, and the lid 4 is held in such a manner that the brushes 14 and 16 provided on the lid 4 come into contact with the commutator. By fitting with the bottom cylindrical body 2, this DC motor can be easily assembled.

Furthermore, this lid body 4 has a through hole 4 for a lead wire. By providing this, it is possible to connect to an external circuit using short lead wires without affecting the armature, field, etc.

Winding element R1a for configuring armature windings R, , R2
+ R1b+ Rlc and R2a, R2,,
The electrical connections related to R2c, the commutator, and the brushes will be explained with reference to FIG. 15.

Winding element Rla+R constituting the first armature winding R1,
,,'R,c are a pair of terminals Rla+A l
a, βlb+ jl! lb, Rll: +*, c, respectively, one of the pair of terminals 11a+LA of this winding element R1& is connected to the commutator electrode S jab and the other to the commutator electrode S Ica, and the winding element R1b A pair of terminals 1.1. β1b has commutator electrode 5tab on one side
The other terminal is connected to the commutator electrode 5lb0, and one of the pair of terminals βlc+LC of the winding element RIC is connected to the commutator electrode Slbc, and the other is connected to the commutator electrode Slb0.
Each is connected to the ca.

As a result, the winding elements R,a, R1b+Rlc constituting the first armature winding R1 are Δ-connected, and each vertex of this Δ-connection is connected to the commutator electrode S+ab, which is arranged substantially at a 120° corner. ,Sob. , S+Ca, respectively, and the brushes B are arranged facing each other at substantially 180° intervals.16. A current from Blb is supplied to one of these winding elements in turn to create a magnet field 8. ．． 8b (FIG. 5) to generate rotational force as a motor, as is well known.

Further, winding element R2a constituting the second armature winding R2
, β2b, R2C and these pair of terminals R2a
+Las Cb, j22bXβ2c+ 12c
and commutator electrodes S 2ab, S 2ab+ S 2
connection with Ca, and further these commutator electrodes S 2ab,
It is clear that the relationship between S 2abl S 2ca and the brushes B2a and B2b is the same as that described for the first armature winding R1, and these first armature windings R and the second armature winding By switching the connection with the child winding R2 as explained with reference to FIG. 1, the rotational speed and rotational torque can be switched.

In this connection state shown in FIG. 15, each brush Bla+
Blb and four lead wires L1.B2a and B2b connected to each other. L2. It is necessary to lead L2' and L3 out of the casing, but this connection can be made by connecting the first armature winding R1 and the second armature winding R2 in series, as shown in FIG. When taking out the conductor from point T23, as shown in FIG. 8, the lead wire L2. By connecting L2' inside the casing, the conductors are led out from this DC motor to Ll, T-2, I-.
It can be made into three pieces.

It goes without saying that as the armature winding in this embodiment, the winding as described above or a modified winding thereof can be used as appropriate.

Fifth Embodiment In the fourth embodiment described above, the two electrodes 14 and 16 were arranged to move together in the axial direction of the motor rotating shaft 12. First view
In the fifth embodiment shown in FIG.
4 is extended in the axial direction of the rotating shaft 120, and a second commutator 16 is fitted via an insulating spacer 28 so as to cover a portion of the rotating shaft 120 in the axial direction, and the first armature winding R1
The first plan Bl& for supplying current to the first
contacts the exposed portion of the commutator 14 of the second armature winding R2.
The second brush B2a is for supplying current to the first brush B2a.
The second commutator 16 was fitted into the commutator 14 of the second commutator 14.

Note that the through hole 16) provided in the spacer 28 is a through hole through which the lower rectifying character 16 passes.

Furthermore, the connection state and assembly of these winding elements, commutators, brushes, lead wires, etc., as well as their functions and effects, are the same as those described above for the fourth embodiment shown in FIG. A detailed explanation thereof will be omitted.

It goes without saying that as the armature winding in this embodiment, the winding as described above or a modified winding thereof can be used as appropriate.

Further, in the above embodiment, the brush and the lead wire are connected inside the motor body, but the present invention is not limited to this, and the lead wire from the brush is connected from the motor body. It is obvious that the brush handle may be pulled out and connected to the conductive wire outside the motor body.

[Application Example] Hereinafter, an application example of an electric circuit of a camera using the DC motor according to the present invention described above for film winding and rewinding will be described.

FIG. 18 shows a block diagram of an electric circuit for controlling the camera used in this application example. In Figure 18,
E is a power supply battery, μC is a microcomputer (hereinafter referred to as a microcomputer) that performs sequence control and exposure calculation for the entire camera, and this microcomputer μC is a diode D1.
Power is supplied from the power supply #E via the power supply. LIvI is a photometry circuit that measures the brightness of a subject by receiving light transmitted through a photographic lens (not shown), and ISO is a filter 1 loaded in the camera.
1 is a film sensitivity automatic reading circuit that automatically reads the sensitivity, AV is an aperture F value reading circuit that reads the aperture F value of the photographic lens loaded in the camera body, and these circuits LM
, Is○, AV are the respective output information as digital apex value signals B v o +Sv, C,. The data is then output to the microcomputer μC.

ΔE is an exposure control circuit that controls the operation of the diaphragm and shutter in accordance with the aperture value signal Av and the shack speed signal 1'V from the microcomputer μC. BC is a harness check circuit that checks the current and voltage when current is passed through a resistor corresponding to the actual load, and based on this voltage, the microcomputer μC determines whether or not it is possible to switch the armature winding of the motor M as described above. make that judgment. MC is a motor control circuit that decodes a 3-bit control signal transmitted from the microcomputer μC to generate a control signal for a motor drive circuit MD that drives the motor M. E, BC, MC to these circuits.

The MD is supplied with power from a power supply E via a power supply transistor Tr. Here, the pace of the power supply transistor Tr+ is changed to the output terminal p of the microcomputer μC via the inverter IN.
v;c is connected to E, BC, MC to the above-mentioned circuit by this microcomputer μC.

Power supply to the MD is controlled. Furthermore, Rr and Or are
These are a resistor and a capacitor, respectively, provided to create a reset signal that is manually input to the input terminal RE of the microcomputer μC when the battery is loaded.

Next, I will explain the switches. SL is an M switch that is turned on by pressing the shirt release button (not shown) up to the first stroke.
A signal changing from the "I" level to the "■" level is input to T, and an interrupt routine TNT, which will be described later, is executed. S2 is a release switch that is turned on when the shirt release button is pressed down to a second stroke, which is longer than the first stroke, and when the release switch S2 is turned on, an exposure control operation is started. S3 is a back cover close switch that is turned on when the back cover of the camera is closed. When this switch S3 is turned on, the interrupt terminal INT2 of the microcomputer μC changes from the "H" level to the "I-" level. The interrupt routine IN, which will be described later, is input manually.
T2 is executed. S.

is a manual selection switch that is set to be turned on or off depending on the manual selection of either the automatic switching mode that automatically switches the drive speed of the motor M or the low speed mode that forcibly sets the drive speed to low speed. Switch S is set to OFF in automatic switching mode and ON in low speed mode. S5 is a switch that is turned on just before the winding of one frame of film is completed. For example, in a configuration where a cam is provided where one rotation corresponds to one frame of film, S5 is turned on just before the cam completes one rotation. It's like a switch. S6 is a switch that is momentarily turned on when winding of one frame of film is completed.

Here, the configuration for winding up one frame of the film used in this application example is provided with a cam for winding up one frame (not shown), and when this cam is rotated once, a winding mechanism (not shown) is activated. works to stop the film winding operation, and
The structure is such that as the load on the winding mechanism increases, another mechanism is operated to turn on the one-frame winding switch S6. Then, the winding mechanism is released at the beginning of the next rotation of the motor M. Therefore, the torque applied to the motor M increases immediately before the winding operation is stopped by the winding mechanism.

Switch S7 is a film detection switch, which is provided on the film running surface (camera body side) on the side into which the film container is inserted, and detects that the film has come out from the film container. The switch S8 is an exposure completion switch that is turned on when the exposure operation is completed and the running of the second curtain of the focal plane shack is completed, and is turned off by a mechanism (not shown) when one frame of the film is wound.

Next, the operation of the above-described configuration will be explained with reference to flowcharts showing the operation of the microcomputer μC shown in FIGS. 19 and subsequent figures. When the battery E is renewed, a reset signal that switches from the "L" level to the "R" (J level) is input to the reset terminal RE of the microcomputer μC, and the microcomputer μC executes the reset routine (RESET) shown in FIG. First, in #1, the microcomputer μC initializes its internal flags and registers, which will be described later, and in #2, the microcomputer μC initializes the output terminals op, .

Set all P2 to "L" level, and set #3 to the built-in terminal I.
The interrupt is enabled by the interrupt signal to NT, , INT2, and its operation is stopped at #4.

In this state, when the Nyatta release button (not shown) is pressed down to the first stroke, the shooting preparation switch S is turned on, and a signal changing from the "H" level to the "L" level is sent to the interrupt terminal INT of the microcomputer μC. , when entered in
The microcomputer μC executes an interrupt routine INT. In this interrupt routine INT, the microcomputer μC first prohibits interrupts to this flow in #5, and #6
turns on the power supply transistor Tr, and connects the power supply line V1.
Through exposure control circuit △E, battery check circuit B
C. Start supplying power to the morke control circuit MC and motor drive circuit MD. Then, in #7, it is determined whether or not the photographing preparation switch S1 is on, and if it is not on, the power supply transistor 1r is turned off in #8.
Proceed to step 3.

If the shooting preparation switch S1 is on in #7,
Exposure information is input in #9, and exposure calculation is performed in #10. Flowcharts of subroutines showing the detailed operation of #9.110 are shown in FIGS. 20 and 21, respectively. First, in the exposure information input subroutine shown in FIG. 20 showing the operation in #9, in #9-1, film sensitivity information Sv is input manually from the film sensitivity automatic reading circuit ISO, and in #9-2, film sensitivity information Sv is manually input from the open F value reading circuit AV. Information regarding the subject brightness measured by inputting the open F value information Δvo and receiving the light transmitted through the photographic lens from the photometry circuit LM in #9-3.
o manually.

On the other hand, in the exposure calculation subroutine shown in FIG. 21 without the operation in #10, the photographing information Sv manually entered in #10-1,
Find the exposure value E y from Avo and Bvo, #10
-2, the control aperture value AV and control shutter speed Tv are calculated based on a predetermined program diagram (not shown).

Returning to FIG. 19, #9 shown in FIGS. 20 and 21. When the operation in #10 is completed, it is detected in #11 whether the shack release button has been pressed to the second stroke and the release switch S2 is turned on, and if the shirt release button is not pressed, the process goes to #7. When the button returns and is pressed down, it jumps to #12 and performs the exposure control operation. Then, in #13, after waiting for this exposure control operation to be completed, the second curtain of the shack runs and once the exposure control operation is completed, the film proceeds to wind one frame.
In this application example, before that, it is determined in #14 whether the drive mode of the motor M is the automatic switching mode or the low speed mode. Here, in #14, manual selection switch S4
It is determined whether the low-speed mode is selected according to the state of , and if the low-speed mode is selected, the flag (O) F) indicating the automatic switching mode is reset in step #15. - When automatic switching motor is selected, in #16, current is passed through the resistance corresponding to the load of motor M and the voltage drop is measured to determine whether battery E can withstand the current consumption when the motor is driven at high speed. Execute the battery check routine to determine the battery.

Before explaining the configuration of the battery check circuit that performs this pantry check and the flowchart showing the battery check operation, we will briefly explain the mechanism for feeding the film when winding one frame of film, and explain the motor drive speed and battery voltage. Explain the relationship between FIG. 22 shows a cell 7 in which the horizontal axis represents the filter feeding time and the vertical axis represents the battery voltage. This will be described below.

First, at the start of film winding, since high torque is required to start winding, voltage is supplied to both the first and second armature windings in order to obtain low speed and high torque. [Zuna] In the conceptual diagram in Figure 1, Switch S
W will be switched to contact t1. Then, after the predetermined time 11 has elapsed, the motor M can be switched to the high speed rotation side. That is, the switch Sw in FIG. 1 is switched to the contact t2 side. This time 1 is set so that the output rotation speed of the motor M reaches a point near the point where the two characteristic lines (T-N) α and (T-N) β intersect with each other in FIG. 2. When the motor is switched to high-speed rotation in this way, the internal resistance of the motor M becomes smaller compared to low-speed rotation as described above, so the voltage may become lower than at the start of high-speed rotation (particularly when the battery capacity is low).

Here, when the voltage of the power supply becomes low, the current that can be passed through the electronic winding decreases, and the required torque cannot be obtained. Therefore, as shown by the curves in FIG. 22, even if an attempt is made to wind the film, the film cannot be wound, and it becomes unclear why the rotation of the motor M was switched to the high speed side. Therefore, in this application example, in order to obtain the current or voltage necessary to obtain the torque required for winding the filter, a predetermined voltage level is set as shown by VR in Fig. 22, and the actual load is If the power supply voltage when current flows through the corresponding resistance is higher than the set voltage level VR, it is assumed that the motor M can be driven efficiently, and the film winding speed is increased by switching to the high speed side, and the open circuit voltage is increased. If V is lower than the voltage level VR, as shown by curve (C) in FIG. 22, high torque is obtained while the rotation speed remains low to ensure film winding.

In this application example, the winding mechanism is used to forcibly stop the film when one frame of film has been wound, so the torque is temporarily large when winding of one frame of film is finished. Become. For this reason, when the motor M is in a high-speed, low-torque rotating state, depending on the state of the battery, the output torque may be insufficient and the motor M may stop rotating in the winding-Ling direction. Therefore, in this application example, the motor M is always switched to the low-speed, high-torque side immediately before the winding of one frame of film is completed to ensure that the motor is driven.

Next, FIG. 23 shows the configuration of the battery check circuit BC that performs the battery check, and FIG. 24 shows the battery check subroutine of #16 in FIG. 19. The second section explains the operation of this battery check subroutine.
To explain with reference to the circuit diagram in Figure 3, first, the microcontroller μ
At #16-1, C outputs a power-on recent signal that becomes -IRHJ from its output terminal OP2, and resets the RS flip-flop R3 shown in FIG.

Next, in #16-2, connect the output terminal ○P1 to several m5ec.
(for example, 2 to 3 m5ec) (at the J level, turn on both transistors Tr2 and 1"r3 shown in FIG. Apply current to #1.
6-3, the voltage Va obtained by dividing the voltage when this current flows is a predetermined reference voltage Vr of 2Hq=voltage #Vr1 (this reference voltage V r l is the voltage level V in FIG. 22). R is the required voltage), and if it is lower, the comparator COMP is
A signal changing to "H" level is output to set the RS flip-flop RS+. As a result, the RS flip-flop R81 outputs r) (J level. On the other hand, when the divided voltage Va of the power supply voltage is higher than the reference voltage Vr1,
Since RSS flip-flop R3 is not set, its output remains at the "L" level. Therefore, R.S.
When the output of the S flip-flop R3 is at the "H" level, it indicates that the voltage of the power supply has decreased to a predetermined value or less, and conversely, when the output is at the rJ-,j level, the power supply voltage is not driving the motor. This shows that the voltage is sufficient for high-speed driving.

Therefore, the microcomputer μC uses transistor T in #16-2.
r2. After turning on Tr3 for several m5ec, #1
In step 6-3, a battery check is performed by checking the output of the R, S flip-flop R81, and when it is determined that the voltage is sufficient based on the result, that is, when the output of the RS flip-flop is at the "L" level, #
16-4 does not indicate the automatic switching mode and sets the flag (auto F) to 1'' and determines that the voltage is not sufficient, that is, the output of the RS flip-flop R3 is
When the HJ level is reached, the automatic switching mode is not indicated in #1.6-5, and the flag (O) F) is reset to 0 to recover.

Returning to FIG. 19, after the drive speed of the motor M has been selected in this way, the microcomputer μC controls the film winding operation in step #17. The subroutine showing this film winding operation is shown in FIG. 25 and will be explained. First, in #17-1, the microcomputer μC inhibits the operation of the interrupt routine 1NTl by turning on the shooting preparation switch S, and #1
7-. At step 2.39, a timer interrupt, which will be described later, is enabled, and at #17-3, timer 1, which will be described later, is reset and started. This timer interrupt occurs when the maximum number of filts that can be taken has been taken and no more filts can be wound.
This is for switching to rewind operation. This timer is a hard timer provided inside the microcomputer μC.

Here, in Table 1, from the microcomputer μC to the motor control circuit M
A 3-bit signal b2. b1+bo
and a 6-bit control signal a output from the motor control circuit MC to the motor drive circuit 1vN,
No relationship with b, c, d,, e, f is shown.

U Table 1 In Table 1, rlJ is "L" level and rH" is "H" level.
” level, “0” does not indicate open, respectively.

Then, #17-ll in Fig. 25 starts the film winding operation, but in the initial stage of the winding operation, the microcomputer μC is activated to rotate the motor M at a low speed.
is the 3-bit signal shown in Table 1 (
],, 0. 0) is output.

ll 2 Then, the motor control circuit MC to which this signal is input,
Control signals a, b, c, d, e
, f and 0. Output O, H, 0, 0 to motor drive circuit MD.

Next, the motor control circuit MC and motor drive circuit MD will be explained. The microcomputer μC sends six types of 3-bit signals to the motor control circuit MC in accordance with the drive to be controlled of the motor M. This is shown in Table 1. Zunawachi,
If it is low speed forward rotation, (b2.b,,bo)-(1,O,
O) is output. This is a human-powered motor control circuit MC.
decodes the input signal and generates the control signal a.

b, c, d, e, f, O,
Output O, H, 0°○ to the motor drive circuit MD.

The motor drive circuit MD has a configuration as shown in FIG. 26, and in low-speed forward rotation, transistors Tr2. Both Tr7 are turned on, and the other transistors are turned off, and the current flows from transistor Tr4 → motor M ((direction of R) → transistor 1゛r7, and motor M
is rotated forward at low speed. Similarly, in low-speed reverse rotation, (b, , b, , b, ) = (1,0,1,
), (a, b, c, d.

e, f)=(◯, H, L, O, O, O), the current flows from transistor Tr6 to motor Ivl (direction of (CI)) to transistor Trs, and motor M is rotated in reverse at low speed. In the case of high-speed forward rotation, (b2゜b,,
ba) = (0,1,O), (a, b, c.

C1,, e, f> = (0,0,0,H,L,
O), and the direction of the current is from transistor Tr6→Moke M→transistor Tr7, and motor M is rotated forward at high speed. Here, in FIG. 26, the signal line coming out from the center of the motor M indicates that it is formed from an intermediate tap. In the case of high-speed reverse rotation, (b2, b,
,bo)=(0,1,],,),(a, b,
c, d, e, f) = (0, H, O,
O.

L, O), and the direction of the current is transistor Tr6→
Mork M becomes transistor Tr9.

The motor is stopped by an NPN transistor T rs , regardless of low/high speed and forward/reverse rotation.
T r7 and T''r9 are all turned on to short-circuit the entire motor R4.The reason is that at low speeds, all two armature windings are used, so naturally the entire two armature windings are On the other hand, in the case of high-speed operation, only one of the two armature windings is used, so some people argue that it is only necessary to short-circuit this armature winding, but if the two armature windings are connected to the coaxial core, Since both armature windings are wound, the other armature winding also rotates around the iron core in the same way as the armature winding through which current is flowing.Then, the armature winding generates an electromotive force. To briefly explain this with reference to Fig. 1, it is assumed that the switch SW in Fig. 1 is now switched to the contact t2 side.As mentioned above, the armature winding R1
, R2 are both rotating, so a predetermined electromotive force (energy) is generated respectively. Even if the power supply to motor M is stopped while this armature winding is rotating, motor M
rotates. At this time, if only the armature winding R2 side is short-circuited, electromagnetic braking will be applied only to the armature winding R2, and inertia energy will be consumed and the rotation will try to stop, but the power generation on the armature winding R1 side Energy does not contribute to electromagnetic braking, resulting in insufficient braking force. Therefore, even if only the armature winding R2 side is short-circuited, the rotation of the motor M will not efficiently stop rapidly. Needless to say, this principle remains the same even if the rotation direction is different. For this reason, when stopping the rotation of the motor M, regardless of the rotation direction and rotation speed,
Short circuit the entire armature winding. As a modification of this, the same effect can be achieved even if only the transistors Trs and Tr7 are turned on (as shown in the bottom row of Table 1).

Returning to the winding subroutine shown in Fig. 25, the microcomputer μC outputs a low-speed forward rotation control signal at #17-4, and then #1
In step 7-5, it is determined whether or not the flag (auto F) indicating automatic switching is set to l''. If it is set, in step #17-6, after counting the predetermined time ■1,
], 7-7 outputs a signal for switching to high-speed forward rotation.

On the other hand, when the flag (AUTO F) is not set, the motor M is driven at a low speed. Then, in #I 7-8, when the switch S5, which is turned on momentarily after winding one frame of film, is turned on, #L7-9
Switch to low-speed forward rotation at #17-10 and wait for switch S6, which indicates the end of one frame winding, to be turned on. When this switch S6 is turned on, stop control of the motor M is performed at #17-11. .

Next, we will explain the subroutine in Fig. 27 which shows the detailed operation of the motor stop step # in Fig. 25 and 7-11. After waiting for the time required for the rotation of motor M to completely stop, a signal for turning off motor M (a signal for turning off transistors Tra to Tr9) is output at step (3). Then, press ■ to stop timer 1, press ■ to disable timer interrupts, and return.

Further, returning to FIG. 19, when winding of the film is completed at #17, the process returns to #7, and the same operation is repeated thereafter.

Next, a description will be given of a timer interrupt for rewinding the film when the number of films that can be photographed ends and the film can no longer be wound during the film winding operation described above. As mentioned above, when a predetermined period of time (for example, 1.5 seconds) has elapsed since the start of timer 1 at the start of winding, the microcomputer μC should perform the film rewinding operation (by running the timer interrupt routine shown in FIG. 28). Execute.

First, in this routine, other interrupts INT, . This subroutine for stopping the motor has been explained previously, so a description thereof will be omitted.

Next, in #102, it is determined whether or not the switch S4 to force the drive of the motor M to a low speed is turned on, and if the low-speed drive motor is selected and the switch S4 is turned on, then in #103 The flag (O) F) indicating automatic switching mode is reset to "0" in #104, and if switch S4 is not turned on, a battery check is performed to determine whether the voltage is sufficient for automatic switching. Proceeding to the subroutine, the motor is controlled during film rewinding according to the motor speed control selected in #105.

The subroutine for this motor control is shown in Fig. 29 and explained. First, in #200, the microcomputer μC outputs a signal indicating low-speed reverse rotation, and in #201, a flag (auto F) indicating automatic switching is set to 1'. Determine whether or not there is one. If this flag (auto F) is not set, proceed to #204; if it is set, proceed to #202, count a predetermined time of 11, and switch the drive of motor M to high-speed reverse rotation in #203. , proceed to #204.

In #204, it is determined by the film detection switch S7 whether or not all the film is stored in the film container and rewinding is completed. If the film is not stored in the container, it is waited for, and if it is stored, in #205 to control the motor stop and return to #7 (S,
Return to step ON).

Next, control of the motor M during initial winding when film is loaded into the camera will be explained.

First, when you close the camera back cover (not shown), switch S3
As a result, the microcomputer μC receives a signal changing from the "■1" level to the r1, J level to its interrupt terminal INT2, and executes the interrupt routine INT2 shown in FIG. In this interrupt routine INT2, the microcomputer μC first prohibits execution of the interrupt routine INT by turning on the imaging preparation switch S at #300.

Next, in #301, initialize the variable N to '0゛°, and in #3
At 02, the power supply transistor Tr is turned on.

Then, in #303, it is determined whether or not a mode in which the motor M is forced to drive at a low speed is selected, and if the low speed mode is selected, or if film is not loaded in the camera in #305. When it is determined, #304
The flag (O) F) indicating automatic switching mode is reset to 0. When it is determined in #303 that the low speed mode is not selected and that film is loaded in #305, a battery check is performed to select the drive speed of motor N/1 in #306, and in #307 controls the motor for initial winding of the film.

A subroutine showing the control of the motor M during this initial hoisting is shown in FIG.
At 01, it is determined whether the flag (O) F) indicating automatic switching mode is set. Here, if this flag (auto F) is not set, the step goes to #404, and if it is set, after a predetermined time is counted in #402, control is performed to switch to high-speed forward rotation in #403.

Then, proceeding to #40/I, the process waits for the switch S5, which is turned on immediately before the end of film winding, to be turned on, and when this switch S5 is turned on, the motor is controlled to rotate at low speed in the forward direction in #405. Then, wait for the winding completion switch S6 to be turned on in #406, and when this switch S6 is turned on, add "1" to the variable N in #407, and check whether this value N has become 3'' in #408. If the variable N is not 3'' in #408, the flag (
Determine whether or not O)F) is set, and if it is set, proceed to #403, drive motor M at high speed forward rotation to wind the film, and flag (O)F)
If it is not set to ``1'', the film is wound at #404 and rotated at low speed. Then, when the variable N becomes ``3'' in #408, that is, the film has been wound up by three frames, the motor M is stopped in #410 to complete the initial winding, and the motor M is stopped in #7 in FIG. Recoup to the flow of.

Below, various modifications of the electric circuit of the camera shown in FIGS. 19 to 31 will be shown.

First, in the application examples shown in Figures 19 to 31, at the initial winding of the film, as in normal one-frame winding,
When the rotational speed of the motor M can be changed, the rotational speed of the motor M is changed to high-speed rotation after a predetermined period of time has elapsed from the start of low-speed rotation. This is because when winding the film around a spool (not shown) during initial winding of the film, it is easier to wind the film around the spool if the motor M is rotated at a low speed rather than at a high speed.

Therefore, in a modified example (not shown below), a switch (hereinafter referred to as SLS switch) that detects when the film is wound around the spool is provided, and the ST, S switches are turned on (the film is not wound around the spool). When the S L S
It is configured to switch to high speed rotation when the switch is turned off (when the film is wound around the spool).

Here, in this SLS switch, for example, the spool is formed of a conductive gob, and a conductive pressing member is provided that contacts the spool from the camera body, and these form a switch. When the film is wound around the spool, the switch is formed. A configuration may be adopted in which the connection between the conductive spool and the conductive suppressing member is broken by the film, and the switch is turned off.

As a flowchart showing the operation of the microcomputer μC to implement this, the one in FIG. 30 may be exactly the same as the previous one, and the step of counting the predetermined time in #402 in FIG. , step D of determining whether the SLS switch is on, waits until the SLS switch is turned off, and when it is turned off, the process advances to #403 and high-speed rotation is started. Furthermore, it is necessary to add this SLS switch and the input terminal of the microcomputer μC that operates it manually to the overall block diagram shown in FIG.

Further, if the initial winding and rewinding of the film are not directly related to photographing, there is no need to perform the film at high speed. If these operations are performed at much lower speeds, there are the following advantages:

(a) Current consumption is small.

(b) The sound is quieter than when moving at high speed.

The configuration for implementing this is simply to eliminate the switching step in the control routine for each motor, so a detailed explanation will be omitted.

Furthermore, in the configurations shown in FIGS. 19 to 31, when switching the drive speed of the motor M from low speed to high speed and from high speed to low speed, the power is turned on after a predetermined time has elapsed and immediately before the end of film winding, respectively. switch S
This was done by turning on 5, but if you configure it like this,
Since there is no parameter for the capacity of the power supply battery, the optimum timing of speed switching for the capacity of the battery cannot be obtained for any given battery. Therefore, in the following modification example, switching from low speed to high speed is performed by monitoring the voltage of the battery that returns after the start of low speed rotation. However, in this modification, in the following cases, the hoisting efficiency is poor as the hoisting time is not fully taken, so the structure is such that the switch is made to -degree high speed rotation and then to low speed rotation.

(a) When the voltage at the moment of switching to high speed rotation is lower than the predetermined voltage, (b) When the voltage at the moment of switching to high speed rotation is higher than the predetermined voltage V2, but within a certain fixed time, the predetermined voltage V, (However, this may not be necessary depending on the predetermined level of voltage V2.)
l>V2.

In addition, if the torque suddenly increases, high-speed, low-torque rotation using a battery with a small capacity is inefficient, so the system is configured to switch from high-speed rotation to low-speed rotation based on the degree of drop in power supply voltage. ing.

The above explanation is summarized in Section 33, where the horizontal axis is the time during film winding, the vertical axis is the voltage, and the battery capacity is shown as a parameter.
Do this referring to the diagram. In FIG. 33, it is assumed that the capacities of the batteries for the respective curves (8), (B), (C), and (D) are (8) > (B) > (C) > (D). Now, when considering how to set the torque of the actual motor M to the optimum point for switching from low speed to high speed, the time required to reach the required torque depends on the capacity of the battery (current that can be drawn). I know that it will change. Conversely, if you know the capacity of the battery, you can know how long it will take to reach the required torque. The capacity of this battery can be determined by detecting the time it takes for the voltage to return to a predetermined level after applying current to the motor M, and by changing this predetermined voltage, the time for each battery capacity can be changed. Can be done.

Therefore, if you decide the predetermined voltage for each capacity so that the time it takes for each capacity battery to return to the predetermined voltage matches the time it takes to reach the required torque,
The optimal point for speed switching can be obtained with respect to changes in battery capacity. However, the individual predetermined voltages vary more or less depending on the capacity of the battery, so if the voltage is determined by taking the equation, the optimal speed switching point can be obtained in most cases. In FIG. 33, the voltage is Vl, and it can be seen that the switching time varies for each capacity of the battery (indicating that the required torque is approximately constant). When the driving speed of the motor M is switched from low to high speed in this way, for a battery with no capacity as shown by curve CD> in Fig. 33, the battery voltage becomes lower than the voltage level V2 and the torque becomes smaller. It takes longer to wind the film than when the motor drive speed is not changed. Therefore, at this time, the speed is immediately switched from high speed to low speed.

Also, in cases such as curve (C) in Figure 33, that is, when the power supply voltage does not return to the predetermined voltage within a predetermined time after switching the motor drive speed, the motor drive speed may not be switched. Since it takes more time than the above, the high speed is switched to the low speed after a predetermined period of time has elapsed. Furthermore, as mentioned above, when the torque suddenly increases, for example, when the torque suddenly increases after the winding mechanism is activated, the necessary torque cannot be obtained at high speed rotation.

With this type of battery, it is necessary to change the rotation speed to low speed to produce high torque. In this modification, this is viewed as a voltage drop.

Therefore, the switch S5, which is turned on immediately before the end of film winding, is not required. Furthermore, since the voltage of the battery is constantly detected during film winding, the Hatteredick circuit is not required in this modification. The circuitry required to implement this modification is shown in FIG. 34 and will be explained below.

? In Figure 434, Compare COMPs.

COMP 6. CO) vDing P7 is that base? Hay voltage \l°1°v'3. v″2 (Vl in Figure 33
+'I'3 and V2 respectively) and the partial voltage of the power supply voltage, and when the two base voltages are higher, the rLj level is output. DFF is D-
A flip-flop launches the output of the comparator COMP7 in response to a latch signal from the microcomputer μC. Note that the microcomputer μC requires a new terminal for inputting these signals and a terminal for outputting the signals.

In this modification, a modification of the winding subroutine for controlling the film winding operation shown in FIG. 25 is shown in FIG. 35 and will be described. In FIG. 35, the microcomputer μC first allows a timer interrupt at #50Q, and resets and starts the timer at #501. Next, in #502, a flag (O) indicating the automatic switching mode of the motor drive speed is set.
The state of F) is determined, and if this flag is not set, the process proceeds to #512 where the motor is controlled to rotate at low speed forward and waits for the film winding to be completed.

On the other hand, when the flag (O) F) is set in #502, the motor M is controlled to perform low-speed forward rotation immediately in #503. And in #504, comparator COM
If the output of P s is "HJ, it is determined whether the power supply voltage has become higher than the predetermined voltage V1, and if it has become higher, #50
Proceed to step 6. If the power supply chamber pressure has not become higher than the predetermined voltage V1, the process goes to #505 to determine whether film winding has been completed, and if film winding has not been completed, the process returns to #504. When the film winding is completed, the process goes to step #514 to proceed to a motor stop subroutine, where motor stop control is performed.

In #506, switching to high-speed forward rotation is performed, and in #507, in order to latch a signal indicating whether or not the power supply voltage at this time is lower than voltage V2 shown in FIG. 32, the latch signal is changed to D-.
Output to flip-flop DFF. And #508
Then, the output of this D-flip-flop DFF is input, and it is determined whether this signal is at the rHJ level or not. If it is at the "L" level, the process advances to #512, and the motor is rotated at a low speed again considering the effectiveness of the motor. On the other hand, if the latched signal is at the "rH" level, the signal goes to #509, and the power supply voltage changes to the reference voltage V within a certain period of time (2) shown in FIG. 33 from the output of the comparator COMP5.
1. If it does not, it is determined that the battery capacity is low and high-speed rotation is unsuitable, and the system passes through #510 and #511 to #512 and switches to low-speed forward rotation. .

On the other hand, in #509, if the power supply voltage becomes higher than the reference voltage V1 within a certain period of time (2), the process proceeds to #515, where it is determined whether or not the power supply voltage is higher than the reference voltage V3.
If the film winding is high, proceed to #516 and continue the film winding operation until the film winding is completed.
In step 514, the process advances to a subroutine for stopping the motor in order to control the stopping of the motor. Here, if the load is increased by the winding stop mechanism or the like and the power supply voltage falls below the reference voltage V2 before the winding of the film is completed, the process shifts from #515 to #512 and switches to low-speed forward rotation. Then, the process waits for the film winding to be completed in #5I3, and when the film winding is completed, the motor is controlled to stop in #514, and the process returns.

In this modification, the reference voltage when switching from low speed to high speed and the reference voltage for determining whether switching to high speed rotation is appropriate are set to the same voltage V1, but different voltages may be used as necessary. The voltage may also be set.

Furthermore, the modification shown in FIG. 36 is similar to that shown in FIG.
This is a modified example of FIG. 5, and the difference from the modified examples of FIGS. 34 and 35 is that when detecting whether it is necessary to switch back to low-speed rotation after switching from low-speed rotation to high-speed rotation, The main feature is that the power supply voltage is not detected all the time, but is detected only after a certain period of time after switching to high speed rotation, and only the power supply voltage at this time is examined.

Comparing the circuit shown in Figure 36 with the circuit shown in Figure 34,
The rest is the same except that the comparator COIvi P7 and the D-flip-flop DFF are omitted. A modified example of the flowchart of the microcomputer μC that controls this is shown in FIG. In the flowchart of FIG. 37, #507 and #508 of the flowchart of FIG.
, respectively - Step #5 of counting 12 for a fixed time
07' and the output of comparator COMP5 is "H".
In place of judgment step #508, which determines whether the output of the comparator COM Ps is "I", the output goes to #515;
It is configured to proceed to 12. Further, #509 to #511 in FIG. 35 are omitted. Other operations are the same as in the flowchart of FIG. 35.

Although the two modified examples shown in FIGS. 34 to 37 utilize switching of the motor drive speed only for film winding, it goes without saying that this may also be used for initial winding and rewinding of the film. stomach.

Effect of 1 shot 8J1] According to the present invention, when high torque driving force is required even at low speed, current is supplied to the first and second armature windings; When torque driving force is required, optimal wiring for the DC motor can be achieved, switching to supply current only to the first or second armature winding.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing the concept of the present invention, Fig. 2 is a graph showing the relationship between the torque generated by the motor, its rotational speed, and current, and Fig. 3 is a DC motor according to the first embodiment of the present invention. Fig. 4 is a front view of the upper casing, Fig. 5 is a cross-sectional view of Fig. 3, Fig. 6 is a longitudinal sectional view thereof, Fig. 7 is a perspective view thereof, Fig. 8 is a FIG. 9 is a longitudinal cross-sectional view showing the second embodiment of the present invention, FIG. 10 is a cross-sectional view thereof, and FIG. 11 is a longitudinal cross-sectional view showing the third embodiment of the present invention. Front view, 12th
The figures are (yellow sectional view, Fig. 13 is a vertical sectional view showing the fourth embodiment of the present invention, Fig. 14 is a longitudinal sectional view showing the fourth embodiment of the present invention.
The figure is a cross-sectional view taken along line B-B, FIG. 15 is a schematic diagram showing the electrical connections, FIG. 16 is a vertical cross-sectional view showing the fifth embodiment of the present invention, and FIG. 17 is a cross-sectional view taken along line C- Top view, 6/I. FIG. 18 is a block diagram showing the electric circuit of a camera that uses the DC motor of the above embodiment for winding and rewinding the film. FIGS. 19 to 21 are flow charts showing the operation of the applied example. The figure is a graph showing the relationship between time and voltage at motor startup, Figure 23 is a circuit diagram showing the configuration of the battery check circuit, Figures 24 and 25 are flowcharts showing the operation of the application example, Figure 26 is a circuit diagram showing the configuration of a motor drive circuit, No. 27
Figures 32 to 32 are flowcharts showing the operation of the applied example, Figure 33 is a graph showing the relationship with the power supply voltage over time when starting the motor in the modified example, Figure 34 is a circuit diagram showing the circuit of the modified example, and Figure 35 is a flowchart showing the operation of this applied example, FIG. 36 is a circuit diagram showing yet another modification, and FIG. 37 is a flowchart showing the operation of this applied example. 8... Magnet field, 10... Armature core, 1.0a,
1.0. . 10o... Radial arm of armature core, R,, R2.
・Two independent sets of armature windings, 12... Armature rotating shaft, 14, 1.6... Commutator, B, , B, ・
...Graph, 2,4.6...Casing, 2. ．． 4.
6. End face of this casing. Patent applicant: Minolta Camera Co., Ltd. 1 Kaimei 63
-23550 (21) Fig. 14 υlb Fig. 29 Fig. 27 Fig. 28 Fig. 31

Claims (4)

[Claims] (1) A DC motor including a magnet field and an armature including two wound sets of armature windings and a commutator, which has a pair of end surfaces through which both ends of the rotating shaft of the armature pass through, respectively. A DC motor comprising a casing, wherein electric wires for supplying power to the first and second armature windings are introduced into the casing of the DC motor from either one of these end faces. (2) A patent claim characterized in that the first armature winding is wound near the axis of the radial arm of the armature core of the armature, and the second armature winding is wound outside of the first armature winding. The DC motor according to item 1. (3) A first commutator connected to the first armature winding and a second commutator connected to the second armature winding are arranged on one side of the rotation axis of the armature. The present invention is characterized in that electric wires for supplying power to the first and second brushes that contact these commutators, respectively, are introduced into the casing of the DC motor from the end face of the casing adjacent to these brushes. A DC motor as described in Range 1. (4) A first commutator connected to the first armature winding and a second commutator connected to the second armature winding are connected to each other across the armature of the rotating shaft of the armature. Electric wires that supply power to first and second brushes that are arranged on opposite sides and contact these first and second commutators, respectively, are inserted into the casing of this DC motor from the end face of one side of the casing. A direct current motor according to claim 1, characterized in that the DC motor is introduced into a motor.