JPH11305302A - Film moving device - Google Patents

Abstract

(57) [Problem] To provide a film moving apparatus capable of reducing the time required for moving a film without a significant increase in cost and reducing variations in film stop positions. Main purpose. SOLUTION: A DC motor 50 driven by electric power supplied from a power supply, a moving mechanism for moving the film 10 in a longitudinal direction by a driving force of the DC motor 50, and a plurality of terminals of the power supply and the DC motor 50 are provided. A switch 120 that is arranged between the first and second states in which the DC motor 50 can be switched between a first state in which power from the power supply is supplied to the DC motor 50 and a second state in which a plurality of terminals of the DC motor 50 are short-circuited;
And a motor control circuit 100 for periodically and alternately switching between the first state and the second state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film moving device used for a film reader and the like.

[0002]

2. Description of the Related Art Generally, in a film reading apparatus, a film in which images are recorded in a large number of frames is loaded, and an image at each frame position is read from the film. To read an image at an arbitrary frame position according to the user's preference, it is necessary to first move the film to position the designated frame position near a predetermined reading start position. A film moving device is used to automate the movement of such a film.

[0003]

In this type of film moving apparatus, it is not necessary to perform precise film positioning or the like, and it is desirable that the apparatus can be manufactured at the lowest possible cost. Therefore, it is preferable to eliminate the need for expensive components and to realize the movement of the film with relatively simple control.

[0004] However, if the stop position of the film deviates significantly from the target position, there is a possibility that a part of the image of the designated frame is missing from the read image. Alternatively, a special position correction is required. Therefore, the film moving device is required to have a capability of stopping the film near the target position. Also, it is preferable that the required moving time from when the user designates an arbitrary frame to when the designated frame of the film is moved to the target position is short. However, if the moving speed is increased to shorten the required moving time, the variation in the film stop position becomes large.

SUMMARY OF THE INVENTION It is a main object of the present invention to reduce the time required for moving a film without significantly increasing the cost of the film moving apparatus, and to reduce the variation in the film stop position.

[0006]

According to a first aspect of the present invention, there is provided a film moving apparatus, comprising: a power supply for supplying power; and a plurality of terminals connected to the power supply, and a DC motor driven by the power supplied from the power supply. And a moving mechanism for moving a film in the longitudinal direction of the film by a driving force of the DC motor, and a moving mechanism disposed between the power supply and a plurality of terminals of the DC motor, wherein the DC motor receives power from the power supply. A switch capable of switching between a first state to be supplied and a second state in which a plurality of terminals of the DC motor are short-circuited; and controlling the switch to control the first state and the second state. And a motor control circuit that alternately and periodically switches between the two.

According to a second aspect of the present invention, in the film moving apparatus according to the first aspect, the motor control circuit determines a ratio of a time between the first state period and the second state period, and is determined. And controlling the switch based on the ratio of the time.

According to a third aspect of the present invention, in the film moving apparatus according to the second aspect, a speed detecting means for detecting a moving speed of the film and outputting a speed signal corresponding to the detected moving speed is further provided. The motor control circuit may determine a ratio of time between the first state period and the second state period based on the speed signal and the determined target speed.

According to a fourth aspect of the present invention, in the film moving apparatus according to the first aspect, an index disposed in a predetermined positional relationship with respect to the image storage area of the film is detected, and an index detection signal is generated in accordance with the detection of the index. And a moving amount measuring unit for measuring the moving amount of the film is further provided, and the motor control circuit holds the first state when starting the driving of the film, In response to the index detection signal, measurement of the movement amount by the movement amount measurement means is started, and after the movement amount measured by the movement amount measurement means reaches a predetermined threshold, the first state and the second state 2 is alternately and periodically switched.

According to a fifth aspect of the present invention, in the film moving device according to the first aspect, an index which is arranged in a predetermined positional relationship with respect to the image storage area of the film is detected, and an index detection signal is generated in accordance with the detection of the index. And a time measuring means for measuring time, wherein the motor control circuit holds the first state when starting driving of the film, and responds to the index detection signal. The time measurement by the time measurement means is started, and after the time measured by the time measurement means reaches a predetermined threshold, the first state and the second state are alternately and periodically changed. Is switched.

According to a sixth aspect of the present invention, there is provided a film moving apparatus for moving a film on which a plurality of frames on which images are recorded are formed in a longitudinal direction of the film, and designating an arbitrary frame of the film as a designated frame. Frame specifying means, and a moving direction for identifying whether the direction of the specified frame to the movement target position with respect to the position of the specified frame specified by the frame specifying means is the first direction or the second direction When the identification result of the identification means and the movement direction identification means is the first direction, the film is moved in the first direction to the vicinity of the movement target position by controlling the movement means, If the identification result of the movement direction identification means is the second direction, the movement means is controlled to move the filter toward the second direction to a position beyond the movement target position. After moving the arm, characterized in that a positioning control means for moving the film to the vicinity of the movement target position toward the first orientation.

According to a seventh aspect of the present invention, in the film moving apparatus according to the sixth aspect, the moving means includes a power supply for supplying electric power, and a plurality of terminals connected to the power supply. A DC motor to be driven, a moving mechanism for moving the film in a longitudinal direction of the film by a driving force of the DC motor, and a moving mechanism disposed between the power supply and a plurality of terminals of the DC motor; A switch capable of switching between a first state in which power is supplied from the power supply and a second state in which power supply to the DC motor is cut off, and controlling the switch to control the first state. And a motor control circuit for alternately and periodically switching between the second state and the second state.

According to an eighth aspect of the present invention, in the film moving apparatus according to the seventh aspect, in the second state, the switch short-circuits a plurality of terminals of the DC motor.
According to a ninth aspect of the present invention, in the film moving device according to the seventh aspect, the motor control circuit determines a ratio of time between the first state period and the second state period, and the determined time period is determined. The switch is controlled based on the ratio of

(Operation) (Claim 1) A first state in which power from a power supply is supplied to the DC motor under the control of the motor control circuit, and a second state in which a plurality of terminals of the DC motor are short-circuited. Are alternately and periodically switched.

In this case, the magnitude of the average power applied to the DC motor is determined by the magnitude of the period in the first state and the magnitude of the second power.
And the magnitude of the driving force of the DC motor is determined. By the way, in order to adjust the average power applied to the DC motor, when the terminals of the DC motor are temporarily opened and the supply power is cut off, the back electromotive force generated in the electric coil inside the DC motor A current flows in the opposite direction due to the influence of. The drive of the DC motor is braked by this current.

The magnitude of the effect of the back electromotive voltage generated in the DC motor differs for each DC motor. Due to the effect of the back electromotive voltage, a large variation occurs in the moving speed of the DC motor. In addition, when the period for supplying power to the DC motor and the period for cutting off the power are shortened, the influence of the back electromotive force becomes greater. However, in order to drive the DC motor smoothly, it is necessary to alternately supply power to the DC motor and cut off the power in a short cycle.

According to the first aspect, in the second state, the plurality of terminals of the DC motor are short-circuited, so that the influence of the back electromotive voltage can be avoided. Accordingly, the variation in the driving speed of the DC motor, that is, the moving speed of the film is reduced. (Claim 2) A motor control circuit determines a ratio of time between the first state period and the second state period, and controls a switch based on the determined time ratio.

The driving speed of the DC motor, that is, the moving speed of the film, is determined according to the time ratio determined by the motor control circuit. (Claim 3) The speed detecting means detects a moving speed of the film and outputs a speed signal corresponding to the detected moving speed. The motor control circuit determines a time ratio between the period of the first state and the period of the second state based on the speed signal and the determined target speed.

According to the third aspect, it is possible to control the moving speed of the film so as to coincide with the target speed. That is, the moving speed of the film can be kept constant. When the braking is applied in a state where the moving speed of the film is constant, the variation in the stop position is reduced. (Claim 4) The index detecting means detects an index, for example, perforation arranged in a predetermined positional relationship with respect to the image storage area of the film, and outputs an index detection signal in accordance with the detection. The moving amount measuring means measures the moving amount of the film.

The motor control circuit holds the first state when driving the film, starts measuring the moving amount by the moving amount measuring means in response to the index detection signal, and controls the moving amount by the moving amount measuring means. After the measured amount of movement reaches a predetermined threshold, the first state and the second state are alternately and periodically switched. Immediately after the start of the driving of the film, the first state is maintained, so that large electric power is applied to the DC motor. That is, the film moves at high speed by the driving force of the DC motor. When the vehicle reaches the predetermined deceleration start position, the first state and the second state are alternately and periodically switched, so that the driving speed of the DC motor is limited.

The deceleration start position is determined by the position of an index such as perforation on the film and the amount of movement of the film after the position is detected. Any position can be set as the deceleration start position. (Claim 5) The index detecting means detects an index arranged in a predetermined positional relationship with respect to the image storage area of the film, for example, perforation, and outputs an index detection signal in accordance with the detection. The time measuring means measures time.

The motor control circuit holds the first state when starting driving of the film, and starts measuring time by time measuring means in response to the index detection signal.
After the time measured by the time measuring means reaches a predetermined threshold, the first state and the second state are alternately and periodically switched. Immediately after the start of the driving of the film, the first state is maintained, so that large electric power is applied to the DC motor. That is, the film moves at high speed by the driving force of the DC motor. When the vehicle reaches the predetermined deceleration start position, the first state and the second state are alternately and periodically switched, so that the driving speed of the DC motor is limited.

The deceleration start position is determined by the position of an index such as perforation on the film and the moving time of the film after the position is detected. Any position can be set as the deceleration start position. (Claim 6) The moving means moves a film on which a plurality of frames on which images are recorded are formed in a longitudinal direction of the film. The frame designating means designates an arbitrary frame of the film as a designated frame in response to an input from a user or the like.

The moving direction identifying means identifies one of the first direction and the second direction in which the movement target position of the designated frame is viewed from the position of the designated frame designated by the frame designating means. When the result of the identification by the moving direction identifying means is the first direction, the positioning control means controls the moving means to move the film in the first direction to near the movement target position. If the identification result of the moving direction identification means is the second direction, the moving means is controlled to move the film toward the second direction to a position beyond the movement target position, and then to the first direction. Is moved toward the vicinity of the movement target position.

If the next frame to be read is randomly designated when the film is stopped at an arbitrary position, the next designated frame is located forward or backward with respect to the current film position. Therefore, it is necessary to move the film forward or backward and stop. In this case, a slight error Δe occurs at the stop position of the film. Also, when moving the film forward or backward from the current position to the movement target position by the shortest distance,
The direction of the error Δe occurring at the film stop position changes according to the moving direction of the film.

That is, an error (+ Δe) generated when the film is moved forward and stopped, and an error (−Δe) generated when the film is moved backward and stopped.
Are misaligned in directions opposite to each other, an error (± Δe) twice as large as Δe occurs in the entire apparatus. Claim 6
Thus, the moving direction of the film immediately before stopping the film near the movement target position is controlled so as to always coincide with the first direction. Therefore, regardless of the positional relationship between the designated frame and the current position, the direction of the error generated at the stop position of the film becomes constant. For this reason, the stop position shift of the film is reduced.

(Claim 7) Under the control of the motor control circuit, a first state in which power is supplied from a power supply to the DC motor and a second state in which power supply to the DC motor is interrupted are alternately and periodically performed. Switch to In this case, the magnitude of the average power applied to the DC motor is determined according to the magnitude of the period in the first state and the magnitude of the period in the second state, and the magnitude of the driving force of the DC motor is reduced. It is determined.

(Claim 8) Since the plurality of terminals of the DC motor are short-circuited in the second state, the influence of the back electromotive voltage of the DC motor can be avoided. As a result, variations in the driving speed of the DC motor are reduced.

(Claim 9) The motor control circuit is provided with the first
The ratio of time between the period of the second state and the period of the second state is determined, and the switch is controlled based on the determined percentage of time. The driving speed of the DC motor, that is, the moving speed of the film, is determined according to the ratio of the time determined by the motor control circuit.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIGS. 1 to 8 and 10 show the structure and operation of a film moving apparatus according to this embodiment.
To FIG. This embodiment corresponds to claims 1 to 4 and claims 6 to 9. FIG. 1 is a block diagram showing a configuration of a main part of a film scanner provided with a film moving device. FIG. 2 is a perspective view showing the carriage 40 of the film scanner of FIG. FIG. 3 shows the motor driver 1
FIG. 20 is an electric circuit diagram showing a first state 20. FIG. 4 is an electric circuit diagram showing a second state of the motor driver 120.

FIG. 5 is an electric circuit diagram showing a third state of the motor driver 120. FIG. 6 shows the motor driver 120.
FIG. 9 is an electric circuit diagram showing a fourth state of FIG. FIG. 7 is a flowchart showing the contents of film movement control in the film scanner of FIG. FIG. 8 is a flowchart showing details of step S24 in FIG. 7 in this embodiment. FIG. 10 is a time chart showing a state change of the motor driver 120 and a current waveform of the DC motor 50 during the PWM control. FIG. 11 is a time chart showing an example of a film moving operation in the film scanner of FIG. 12 to 1
4 is a plan view showing a frame position and a target stop position on the film.

In this embodiment, the power supply, the DC motor, the switch and the motor control circuit correspond to the power supply unit 125, the DC motor 50, the motor driver 120 and the main control unit 100, respectively.

The speed detecting means according to the third aspect corresponds to the film movement amount sensor 31 and the main control unit 100. Further, the index detecting means of claim 4 corresponds to the perforation detection sensor 32. The moving amount measuring means according to claim 4 comprises a film moving amount sensor 31 and a main control unit 1.
Corresponds to 00. The moving means and the frame designating means in claim 6 correspond to the DC motor 50 and the host computer 200, respectively. The moving direction identification means and the positioning control means in claim 6 correspond to the main control unit 100.

The power supply, DC motor, switch and motor control circuit of the present invention correspond to the power supply unit 125, DC motor 50, motor driver 120 and main control unit 100, respectively. In a film scanner shown in FIG. 1, a film original 10 photographed and developed by a camera is used.
Is used as a manuscript. Both the positive film and the negative film can be used as the film original 10. When the image is not read, the film document 10 is housed in the cartridge 11 in a state of being wound in a roll shape.

The cartridge 1 shown in FIG.
When the cartridge 1 is loaded, one end of the film original 10 is pulled out from the entrance 11a of the cartridge 11 via a shutter (not shown). Then, the film original 10 is sent in the direction of the arrow x1 or x2 along the X axis. A film movement amount sensor 31, a perforation detection sensor 32, a light source unit 41, a lens 42, and a one-dimensional image sensor 43 are provided around the transport path of the film original 10.

The light source unit 41, the lens 42 and the one-dimensional image sensor 43 are mounted on a carriage 40 shown in FIG. The carriage 40 is movable in the directions of the arrows x1 and x2 along the X axis. As shown in FIG. 2, the light source unit 41 is fixed on a side plate 40a of the carriage 40. On the illumination base 41a of the light source unit 41, an LED block 44, a condenser lens 41b, and an optical path conversion mirror 41c are provided.

The light emitted from the light emitting diode built in the LED block 44 is supplied to the condenser lens 41b.
Then, the light passes through the optical path conversion mirror 41c and heads toward the film original 10 below. This illumination light is applied to the Y
Simultaneously illuminate one axial line. In this example, in order to enable reading of a color image, the LED block 44 is used.
Have three built-in light emitting diodes that emit light of R (red), G (green) and B (blue) wavelengths, respectively.

The light transmitted through the film original 10 is focused on the light receiving surface of the one-dimensional image sensor 43 by the lens 42. The intensity of light to be imaged changes according to the light transmittance of the film original 10, that is, an image on the film original 10. Therefore, the data of one line in the Y-axis direction constituting the image on the film original 10 is transferred to the one-dimensional image sensor 43.
Can be read by Each time one line of image is read, the carriage 40 moves in the X-axis direction by a predetermined amount.
Sub-scanning is controlled. Therefore, the one-dimensional image sensor 43
Is repeated, two-dimensional images on the film original 10 can be sequentially read.

In this film scanner, when reading an image on the film original 10, the position of the film original 10 is fixed, and the carriage 40 is moved in the X-axis direction to move one frame (one frame) of the two-dimensional image. Read. Prior to reading an image, the film document 10 moves in the X-axis direction in order to match the position of a desired image frame on the film document 10 with the position of a predetermined image reading range.

Since the carriage 40 is mechanically connected to the stepping motor 45 shown in FIG. 1, when the stepping motor 45 is driven, the carriage 40 is moved by an arrow x1.
Move in the direction or x2 direction.

Further, as shown in FIG.
When the DC motor 50 is driven, the film original 10 loaded in the cartridge 11 moves in the direction of the arrow x1 (winding direction) or the direction of the arrow x2 (feeding direction). In addition,
A take-up mechanism (not shown) is provided to take up the film original 10 fed from the cartridge 11. This winding mechanism is also connected to the drive shaft of the DC motor 50.

As shown in FIGS. 12 to 14, a large number of image storage areas 14 formed on the film original 10 are arranged at regular intervals in the X-axis direction. Further, each image storage area 14
Beside perforations 16 and 17 respectively
Are formed. Each image storage area 14 on the film original 10 is distinguished by a frame position number. Actually, 1, 2, 3,
The numbers 4,... Are assigned to each frame.

12 to 14, the reference numerals of the large number of image storage areas 14, the perforations 16 and 17, and the numbers of the frame positions to which they are assigned are attached together with parentheses to indicate the distinction between frames. In the following description, when it is necessary to distinguish the frame positions, the respective symbols are distinguished by adding the frame position numbers together with parentheses.

It should be noted that, as shown in FIGS. 12 to 14, the position where each perforation 16 is formed is slightly displaced in the direction of arrow x2 from the position of the frame assigned to it. For example, in FIG.
The perforation 16 (1) of the third frame is formed at a position shifted from the image storage area 14 (1) in the direction of the arrow x2.

A perforation detection sensor 32 shown in FIG. 1 is arranged at a position facing the passage of each of the perforations 16 and 17. The perforation detection sensor 32 is a transmission type optical sensor. The perforation detection sensor 32 incorporates a light source and a light receiving element arranged at positions facing each other with the film document 10 interposed therebetween.

The perforation 1 is located at a position facing the perforation detection sensor 32 of the film original 10.
The light reception level of the perforation detection sensor 32 changes depending on whether or not there are the pixels 6 and 17. Based on the light receiving level, the perforation detection sensor 32 identifies whether or not the perforations 16 and 17 exist at positions facing the perforation detection sensor 32.

The film movement sensor 31 shown in FIG.
A disk that rotates with the movement of the film original 10 and an optical sensor that outputs a pulse signal every minute rotation of the disk are built in. Outputs of the film movement amount sensor 31 and the perforation detection sensor 32 are transmitted to the main control unit 1 via the system bus 105 in the form of binary signals.
00 is input.

The electrical unit of the film scanner shown in FIG. 1 includes a main control unit 100, a memory unit 110, motor drivers 120 and 130, a sampling unit 1
40, A / D conversion unit 150, gradation conversion table 1
60, a timing control unit 170, an LED driver 180, and an interface unit 190.

The host computer 200 is connected to the film scanner via the interface unit 190.
Is connected. The host computer 200 is a personal computer having a general configuration. The host computer 200 has a control program for executing image input using the film scanner of FIG.

The main control unit 100 includes the system bus 1
05, a memory unit 110, motor drivers 120 and 130, a gradation conversion table 160, a timing control unit 170, and an interface unit 190.
And are connected to each other. The main control unit 100 includes a microcomputer for control. The main control unit 100 controls the overall operation of the film scanner shown in FIG. 1 according to a program stored in the internal memory.

The memory unit 110 is mainly used to temporarily hold digital data of a two-dimensional image read from the film original 10. The memory unit 110 has a memory capacity capable of storing data of a plurality of frames of a two-dimensional color image. The motor driver 120 controls electric power applied to the stepping motor 50 according to a control signal from the main control unit 100. As shown in FIGS. 3 to 6, the motor driver 120 includes four switching elements SW1 to SW4 that are independently turned on / off.

In practice, the switching elements SW1 to SW4
Are each composed of a transistor. Control signals from the main control unit 100 are applied to control input terminals of the switching elements SW1 to SW4. DC motor 5
0 terminals 50a and 50b
The power supply unit 125 is connected to power supply lines 125a and 125b via the three switching elements SW1 to SW4.

In this embodiment, if necessary, the motor driver 120 operates the first state shown in FIG. 3, the second state shown in FIG. 4, the third state shown in FIG. 5, and the fourth state shown in FIG. It is used in four types of states. The power supply unit 12
5 is omitted in FIG. Motor driver 130
Controls the power applied to the stepping motor 45 according to a control signal from the main control unit 100.

The sampling unit 140 extracts a signal component of each pixel from an analog image signal output from the one-dimensional image sensor 43 according to a control signal output from the timing control unit 170. The sampling unit 140 is a CDS (Correlated Double Sampli
ng) built-in sampling circuit. The sampling unit 140 also includes a circuit for performing processing such as shading correction, dark current correction, and even / odd number correction.

The A / D conversion unit 150 synchronizes with the control signal from the timing control unit 170,
Perform the conversion. That is, the level of the analog image signal output from the sampling unit 140 is converted into an 8-bit digital value. The gradation conversion table 160 is
It is composed of a readable and writable memory. The contents of this memory are updated by the main control unit 100. The correlation between the input and output of the gradation conversion table 160, that is, the conversion characteristic changes according to the content of the data written in the memory.

The gradation conversion table 160 corrects the gradation characteristics of the digital image data output from the A / D conversion unit 150. The conversion result of the gradation conversion table 160 is output to the memory unit 110. The gradation conversion table 160 is associated with each color of R, G, and B.
It has three sets of conversion tables. According to a control signal from the timing control unit 170, any one set of conversion tables is selected.

The timing control unit 170 generates various timing signals necessary for image reading according to the control signals given from the main control unit 100. These timing signals are sent to the one-dimensional image sensor 43, the memory unit 110, the sampling unit 140, the A / D
Conversion unit 150, gradation conversion table 160, and LE
Applied to the D driver 180.

The LED driver 180 controls the light source unit 41 according to a control signal from the timing control unit 170. That is, the switching of the lighting of the light source unit 41 is switched on and off, and the emission colors (R, G, B) are switched. The interface unit 190 is an interface (SCSI) according to a standard. A host computer 200 is connected to the film scanner of FIG.

When an original image is actually read using the film scanner shown in FIG.
0, the film scanner is controlled by an instruction from a predetermined image reading program executed. The host computer 200 responds to the input from the user and gives the film scanner information on the position of the frame to be read and a reading start instruction to the film scanner.

In the processing executed by the main control unit 100, the contents of the control relating to the movement of the film original 10 are shown in FIG.
Shown in The contents of each step in FIG. 7 will be described. When the power of the film scanner is turned on, step S11 is first executed. In step S11, the film document 10 is positioned in an initial state. That is, when the cartridge 11 having the film original 10 is loaded at a predetermined position on the film scanner, the DC motor 50 is driven to feed out the film original 10 from the cartridge 11,
The film original 10 is positioned at a predetermined position and stopped.

Further, before positioning the film original 10, the film original 10 is fed out to the position of the last frame. Then, the number of perforations 16 detected by the perforation detection sensor 32 while the film original 10 is being sent from the leading end to the last frame is counted. From this counting result, the maximum number of frames of the film document 10 is identified.

In step S12, a frame number Fc used to grasp the current position is initialized. For example, when the film document 10 is stopped at a position where the image storage area 14 (2) of the second frame of the film document 10 coincides with the image reading range 18 as shown in FIG. Set 2 Step S1
3, the main control unit 100 receives input from the user through the host computer 200 and the interface unit 1.
Read via 90.

In step S14, it is determined whether or not the user has designated a frame position as a result of the processing in step S13. If the frame position is specified by the user, the process proceeds from step S14 to S15. In step S15, the designated value Fs of the frame position input in step S13 is compared with the frame number Fc indicating the current film position. If the designated value Fs of the frame position is smaller than the frame number Fc, step S16
Proceed to. Conversely, when the frame position designation value Fs is larger than the frame number Fc, the process proceeds to step S19.

In step S16, the driving direction of the DC motor 50 is set to the direction (x1) in which the film original 10 is wound by the cartridge 11. Then, full-speed driving of the DC motor 50 is started. For example, the frame number Fc
When the first frame is designated as the designated value Fs in the case where is 2 (the state of FIG. 12), since (Fs <Fs), the image storage area 14 (1) is required to be aligned with the image reading range 18. The film original 10 is moved in the x1 direction.

Actually, the motor driver 120 is held in the first state shown in FIG. 3, and the power of the power supply unit 125 is supplied to the DC motor 50. Therefore, the power supply unit 12
5 at a maximum speed determined by the voltage of the DC motor 5, the performance of the DC motor 50, the size of the load of the DC motor 50, and the like.
0 is driven. In step S17, the perforation 16 is detected with reference to the signal output from the perforation detection sensor 32. Further, every time the perforation 16 is detected, the value of the frame number Fc is updated (−
1) Yes. Therefore, the frame number at the current film position is held in the frame number Fc.

In step S18, the frame number Fc is compared with (Fs + 1). If they do not match,
Returning to step S17, the process is repeated. When the frame number Fc matches (Fs + 1), the process proceeds to step S24. For example, when the first frame is designated as the designated value Fs when the frame number Fc is 4 (the state of FIG. 13), the perforation 16 (2) of the second frame is perforated as shown in FIG. When the detection by the detection sensor 32, that is, when the film original 10 has advanced to one frame before the target position, the process proceeds to step S24.
Proceed to.

In step S19, the driving direction of the DC motor 50 is set to the direction (x2) in which the film original 10 is unwound from the cartridge 11. Then, full-speed driving of the DC motor 50 is started. For example, frame number F
If c is 2 (the state of FIG. 12) and the fourth frame is designated as the designated value Fs, (Fs> Fs),
The film original 10 is moved in the x2 direction to align the image storage area 14 (4) with the image reading range 18.

Actually, the motor driver 120 is kept in the third state shown in FIG. 5, and the power of the power supply unit 125 is supplied to the DC motor 50. Therefore, the power supply unit 12
5 at a maximum speed determined by the voltage of the DC motor 5, the performance of the DC motor 50, the size of the load of the DC motor 50, and the like.
0 is driven. In step S20, the perforation 16 is detected with reference to the signal output from the perforation detection sensor 32. Further, every time the perforation 16 is detected, the value of the frame number Fc is updated (+
1) Yes. Therefore, the frame number at the current film position is held in the frame number Fc.

In step S21, the frame number Fc is compared with (Fs + 1). If they do not match,
Returning to step S20, the process is repeated. When the frame number Fc matches (Fs + 1), the process proceeds to step S22. For example, when the third frame is designated as the designated value Fs when the frame number Fc is 2 (the state of FIG. 12), the perforation 16 (4) of the fourth frame is perforated as shown in FIG. The process proceeds to step S22 when the detection sensor 32 detects, that is, when the film document 10 has advanced beyond the target position to one frame ahead of the target position.

In step S22, the DC motor 50 is braked to stop the movement of the film original 10. That is, the motor driver 120 is held in the second state shown in FIG. As a result, the power supply to the DC motor 50 is cut off, and at the same time, the terminals 50a and 50b are short-circuited, so that the DC motor 50 is braked. Immediately after the DC motor 50 stops, the next step S23 is executed.
In step S23, similarly to step S16, the driving direction of the DC motor 50 is set to the direction in which the film document 10 is wound, and the full-speed driving of the DC motor 50 is started.

Accordingly, the direction (x1 / x2) of moving the film original 10 immediately after the designated value Fs is designated depends on the frame number Fc and designated value F when the designated value Fs is designated.
Although it changes according to the magnitude relationship with s, the film original 10 is always driven in the x1 direction when proceeding to step S24. By this control, the error of the stop position of the film document 10 is reduced. In addition, since it is always shifted in the same direction, correction becomes possible. In other words, the stop position may be offset by that amount in anticipation of the shift amount from the beginning.

FIG. 8 shows the details of the "film stop control" in step S24. The contents of each step in FIG. 8 will be described below. In step S31, measurement of the movement amount Lx of the film document 10 is started. Thereafter, the moving amount Lx of the film document 10 is sequentially obtained based on the moving speed and the elapsed time obtained from the pulse period of the pulse signal output from the film moving amount sensor 31.

When step S31 is executed, the movement amount Lx is cleared to zero. Accordingly, the moving amount Lx is set at the frame position of the frame number (Fs + 1).
This represents the amount of movement of the film original 10 since the time when 0 is reached. In step S32, the current movement amount Lx is compared with a predetermined threshold value Ls. While (Lx <Ls), the process of step S32 is repeated. When the movement amount Lx becomes equal to or more than the threshold value Ls, the process proceeds to step S33.

For example, when positioning the image storage area 14 (3) of the third frame of the film original 10 in the image reading range 18, the perforation 1 shown in FIG.
When the movement amount Lx of the film document 10 after the perforation detection sensor 32 detects 6 (4) reaches the threshold value Ls, the process proceeds to step S33. In step S33,
Change the control mode of DC motor 50 to PWM (pulse width modulation)
Switch to speed control.

In this PWM speed control, as shown in FIG. 10, the motor driver 120 is alternately switched between the first state shown in FIG. 3 and the second state shown in FIG. A control cycle T0 that repeats switching between the first state and the second state
Is constant in this example. The size of the period Ta in the first state and the second period Tb in one control cycle T0
Is variable in size. When the ratio between the periods Ta and Tb is adjusted, the average power supplied to the DC motor 50 in the control cycle T0 changes, so that the driving force of the DC motor 50 changes.

In this PWM speed control, the sizes of the periods Ta and Tb are automatically adjusted so that the moving speed of the film document 10 matches the predetermined target speed Vo. In order to perform the PWM speed control, the actual moving speed Vc of the film original 10 is sequentially calculated based on the pulse period of the pulse signal output from the film moving amount sensor 31.

Then, the period T is determined based on the magnitude relationship between the target speed Vo and the moving speed Vc and the magnitude of the difference therebetween.
The sizes of a and Tb are automatically adjusted. By the way, in the second state used in the PWM speed control, the switching elements SW3 and SW4 are both turned on as shown in FIG. 4, so that the terminals 50a and 50b of the DC motor 50 are turned on.
Are short-circuited.

The PWM speed control can be performed by using the fourth state (terminals 50a and 50b open) shown in FIG. 6 instead of the second state shown in FIG. However, when the PWM speed control is performed using the fourth state, as shown by the phantom line in FIG. 10, when the current of the DC motor 50 is cut off, a current in the reverse direction flows due to the influence of the back electromotive force. Especially,
In order to drive the DC motor 50 smoothly, the control cycle T0
Is shortened, the effect of the back electromotive force increases accordingly. Further, the stop position of the film document 10 changes due to the influence of the back electromotive voltage. Since the magnitude of the effect of the back electromotive voltage differs for each motor, the stop position of the film document 10 varies.

Therefore, in this embodiment, as shown by the solid line in FIG. 10, PWM speed control is performed using the first state and the second state. When the second state is used instead of the fourth state, the influence of the back electromotive voltage does not appear, so that the variation in the stop position of the film document 10 is suppressed. In step S34 of FIG. 8, the perforation detection sensor 3
2 is monitored to check whether or not the perforations 16 have been detected. When the perforation 16 is detected, the frame number Fc is updated (−1).

In step S35, the frame number Fc is compared with the designated value Fs of the frame position. If they do not match, the process returns to step S34 to repeat the above processing. When the frame number Fc matches the designated value Fs of the frame position, that is, when the image storage area 14 of the designated frame reaches the image reading range 18, the process proceeds to the next step S36.

In step S36, the DC motor 50 is braked to stop the movement of the film original 10. That is, the motor driver 120 is held in the second state shown in FIG. Thereby, the terminals 50a, 5 of the DC motor 50 are
Since 0b is short-circuited, the DC motor 50 enters a full brake state and stops in a short time. After the DC motor 50 stops, the motor driver 120 may be switched to the fourth state.

FIG. 11 shows an example of the operation from the input of the designated frame position value Fs to the stop of the movement of the film original 10 to the designated frame position. In this embodiment, the movement of the film when the film original 10 of the IX240 specification is used has been described. However, the present invention can be similarly applied to the case of moving another type of film.

(Second Embodiment) This embodiment is a modification of the first embodiment, and corresponds to step S24 in FIG.
Is changed to the contents of FIG. Other configurations and operations are the same as those of the first embodiment. This embodiment corresponds to claim 5. In this embodiment, the time measuring means and the motor control circuit in claim 5 correspond to the main control unit 100.

In step S41 of FIG. 9, a timer built in main control unit 100 is controlled to control
The measurement of the movement time Tx of 0 is started. When executing step S41, the movement time Tx counted by the timer is cleared to zero. Accordingly, the moving time Tx is set at the frame position of the frame number (Fs + 1).
Represents the elapsed time since the arrival of.

In step S42, the current travel time Tx
Is compared with a threshold Ts. As long as the value of the movement time Tx is smaller than the threshold value Ts, the process of step S42 is repeated.
When the movement time Tx reaches the threshold Ts, step S33
Proceed to. The value of the threshold value Ts is determined based on the moving speed of the film document 10 detected when step S41 is performed. That is, when the moving distance of the film document 10 after the detection of the perforation 16 of the (Fs + 1) frame has reached the predetermined amount (Ls), step S33 is performed.
The threshold Ts is determined so as to proceed to.

[0086]

According to the present invention, the plurality of terminals of the DC motor are short-circuited in the second state, so that the influence of the back electromotive voltage can be avoided. Accordingly, the variation in the driving speed of the DC motor, that is, the moving speed of the film is reduced.

(Claim 2) The drive speed of the DC motor can be adjusted. (Claim 3) It is possible to control the moving speed of the film so as to coincide with the target speed. Therefore, the moving speed of the film can be kept constant. When the braking is applied in a state where the moving speed of the film is constant, the variation in the stop position is reduced.

(Claim 4) An arbitrary position can be set as the deceleration start position without being restricted by the position of the index such as perforation. By moving the deceleration start position closer to the target stop position, the time required for moving the film is reduced. (Claim 5) An arbitrary position can be set as the deceleration start position without being restricted by the position of the index such as perforation. By moving the deceleration start position closer to the target stop position, the time required for moving the film is reduced. Further, it is not necessary to detect the moving distance.

(Claim 6) Control is performed such that the moving direction of the film immediately before stopping the film near the movement target position always coincides with the first direction. Therefore, regardless of the positional relationship between the designated frame and the current position, the direction of the error generated at the stop position of the film becomes constant. For this reason, the stop position shift of the film is reduced.

(Claim 7) The magnitude of the driving force of the DC motor can be controlled. (Claim 8) Since the plurality of terminals of the DC motor are short-circuited in the second state, the influence of the back electromotive voltage of the DC motor can be avoided. As a result, variations in the driving speed of the DC motor are reduced.

(Claim 9) The drive speed of the DC motor can be adjusted by the ratio of the time determined by the motor control circuit.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a main part of a film scanner.

FIG. 2 is a perspective view showing a carriage 40 of the film scanner of FIG.

FIG. 3 is an electric circuit diagram showing a first state of the motor driver 120.

FIG. 4 is an electric circuit diagram showing a second state of the motor driver 120.

FIG. 5 is an electric circuit diagram showing a third state of the motor driver 120.

FIG. 6 is an electric circuit diagram showing a fourth state of the motor driver 120.

FIG. 7 is a flowchart showing the contents of film movement control in the film scanner of FIG. 1;

FIG. 8 shows step S2 of FIG. 7 in the first embodiment.
6 is a flowchart showing the details of Example No. 4.

FIG. 9 shows step S2 of FIG. 7 in the second embodiment.
6 is a flowchart showing the details of Example No. 4.

FIG. 10 is a time chart showing a state change of the motor driver 120 and a current waveform of the DC motor 50 during PWM control.

FIG. 11 is a time chart showing an example of a film moving operation in the film scanner of FIG. 1;

FIG. 12 is a plan view showing a frame position and a target stop position on a film.

FIG. 13 is a plan view showing a frame position and a target stop position on a film.

FIG. 14 is a plan view showing a frame position and a target stop position on a film.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Film original 11 Cartridge 14 Image storage area 16, 17 Perforation 18 Image reading range 31 Film movement sensor 32 Perforation detection sensor 40 Carriage 40a Side plate 41 Light source unit 41a Illumination base 41b Condenser lens 41c Optical path conversion mirror 41d Illumination lid 42 Lens 431 Dimensional image sensor 44 LED block 45 Stepping motor 50 DC motor 100 Main control unit 105 System bus 110 Memory unit 120, 130 Motor driver 125 Power supply unit 140 Sampling unit 150 A / D conversion unit 160 Gradation conversion table 170 Timing control unit 180 LED Driver 190 Interface unit 200 Host computer W1, SW2, SW3, SW4 switching element

Claims (9)

[Claims] 1. A power supply for supplying electric power, a DC motor having a plurality of terminals connected to the power supply and driven by electric power supplied from the power supply, and driving the film by the driving force of the DC motor. A moving mechanism that moves in the longitudinal direction of the DC motor; a first state in which the DC power is supplied to the DC motor from the power supply and a plurality of terminals of the DC motor; A switch capable of switching between a second state in which a plurality of terminals are short-circuited; and a motor control circuit that controls the switch to alternately and periodically switch between the first state and the second state. A film moving device, comprising: 2. The film moving apparatus according to claim 1, wherein the motor control circuit determines a ratio of a time between the first state period and the second state period, and the determined time period is determined. Wherein the switch is controlled based on the ratio of the film moving device. 3. The film moving apparatus according to claim 2, further comprising speed detecting means for detecting a moving speed of the film and outputting a speed signal corresponding to the detected moving speed, and the motor control circuit. Determining a time ratio between the first state period and the second state period based on the speed signal and the determined target speed. 4. The film moving device according to claim 1, wherein an index disposed in a predetermined positional relationship with respect to the image storage area of the film is detected, and an index detection signal is output in accordance with the detection of the index. An index detecting means, and a moving amount measuring means for measuring the moving amount of the film are further provided, and the motor control circuit holds the first state when starting driving of the film, and the index detecting signal Starts the measurement of the moving amount by the moving amount measuring means in response to the first state and the second state after the moving amount measured by the moving amount measuring means reaches a predetermined threshold value. Characterized in that the film moving device alternately and periodically switches between and. 5. The film moving device according to claim 1, wherein an index disposed in a predetermined positional relationship with respect to the image storage area of the film is detected, and an index detection signal is output in accordance with the detection of the index. An index detecting unit and a time measuring unit for measuring time are further provided, and the motor control circuit holds the first state when starting driving of the film, and responds to the index detection signal to maintain the first state. Start time measurement by time measurement means,
The film moving device, wherein the first state and the second state are alternately and periodically switched after the time measured by the time measuring means reaches a predetermined threshold. 6. A moving means for moving a film on which a plurality of frames on which images are recorded is formed in a longitudinal direction of the film; a frame specifying means for specifying an arbitrary frame of the film as a specified frame; Moving direction identifying means for identifying whether the direction of the designated frame to the movement target position with respect to the position of the designated frame designated by the designating means is a first direction or a second direction; If the identification result of the identification means is in the first direction, the film is moved in the first direction to the vicinity of the movement target position by controlling the movement means, and the identification result of the movement direction identification means is obtained. When the film is in the second direction, the moving means is controlled to move the film toward the second direction to a position beyond the movement target position, and then the first direction And a positioning control means for moving the film toward the vicinity of the movement target position. 7. The film moving apparatus according to claim 6, wherein the moving means includes a power supply for supplying power, and a plurality of terminals connected to the power supply, and is driven by the power supplied from the power supply. A DC motor, a moving mechanism for moving the film in a longitudinal direction of the film by a driving force of the DC motor, and a moving mechanism disposed between the power supply and a plurality of terminals of the DC motor; A switch capable of switching between a first state in which power is supplied to the DC motor and a second state in which power supply to the DC motor is interrupted; controlling the switch to control the first state and the second state. And a motor control circuit for alternately and periodically switching between the two states. 8. The film moving device according to claim 7, wherein the switch short-circuits a plurality of terminals of the DC motor in the second state. 9. The film moving device according to claim 7, wherein the motor control circuit determines a time ratio between the first state period and the second state period, and the determined time period Wherein the switch is controlled based on the ratio of the film moving device.