JPS59204829A - Automatic film feeding device of disk camera - Google Patents

Abstract

PURPOSE:To realize an advantage which is remarkably excellent in comparison with the conventional in respect of space, the number of parts, cost, noise, etc. by using an ultrasonic motor as an automatic film feeding means of a disk camera. CONSTITUTION:An electrostrictive element 12 to which an electrode 14 is attahced is provided on an elastic ring 11b; a rotor 10c is rotated by a surface wave by the electrostrictive element 12, and an ultrasonic motor is constituted of these members 10c, 11b and 12. A rotating member 3c is driven by the rotor 10c, and a film disk 7 is rotated through a charge spring 4. Therefore, a motor small in thickness is formed in a disk shape, a large advantage is generated in respect of a space, also the number of parts can be reduced remarkably, and also it is possible to obtain a disk camera which is remarkably excellent in comparison with a conventional one in respect of a cost and a noise.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to an automatic film feed device for a disk camera having a built-in motor.

(Background of the Invention) In recent years, a so-called disc camera, which uses a ring-shaped film on a disc-shaped substrate, has been commercialized in place of the conventional 35-film film, with the aim of simplifying the development process. Because the film is mounted on a disc-shaped substrate, the film requires less space to load in the camera body than conventional 35mm film, and it has another major advantage: it can provide a thin, compact camera. There is.

For such a compact camera, it is desirable that various functions such as focus alignment and film advance be automated for ease of operation, and a small motor is required for automatic film advance. , are being built into the camera body.

However, since these motors use electromagnetic force, there are significant restrictions on shape and materials, and they require many conversion gears for deceleration, etc., leaving problems in terms of efficiency and noise. Ta.

In response to this situation, actuators have been developed to replace the conventional 1iL magnetic motor, and one type of actuator is a motor that uses ultrasonic waves. Motors using ultrasonic waves are said to be significantly more advantageous than conventional motors in terms of size, shape, efficiency, cost, etc.

Prototype examples of motors that utilize ultrasonic waves (hereinafter referred to as ultrasonic motors) include a vibrating piece type that uses a piezoelectric body to vibrate a vibrating piece ultrasonically to drive a rotor, and a vibrating piece type that drives a rotor by ultrasonic vibration of a vibrating piece using a piezoelectric body, and a vibrating piece type that drives a rotor by ultrasonic vibration of a vibrating piece using a piezoelectric body, and a vibrating piece type that drives a rotor by ultrasonic vibration of a vibrating piece using a piezoelectric body. surface waves (Rayleigh)
A surface wave type has been devised that generates waves (waves) to drive a pressed moving object.

In particular, regarding the latter type of surface wave type ultrasonic motor, in 1964, the SI at Bell Laboratories was developed as a method for generating surface waves.
Since the interdigital transducer was devised by TTIG, it has become possible to easily achieve highly efficient mutual conversion between electrical energy and ultrasonic vibration energy (surface waves). By changing the
Since it uses surface waves, it has the advantage of being able to output low rotation and high torque.

An object of the present invention is to provide a disk camera that is significantly superior to conventional ones in terms of space, number of parts, cost, noise, etc. by using an ultrasonic motor as an automatic film feeding means for the disk camera. do.

(Example) Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 shows a disk-shaped substrate (
This is an example of a conventional disc camera having a motor for driving a film disc (hereinafter referred to as a film disc). In the figure, the driving force of a motor 1 that rotates using electromagnetic force is transmitted to a gear train 3 by a pinion gear 2, and drives a gear 3a arranged so that its rotation center coincides with the rotation center of the film disk, The gear 3a rotates the rotating member 5 which engages with the unwinding engaging member 6 disposed at the center of rotation of the film disk 7 via the charge spring 4.1. The operation will be briefly described below.

When the motor 1 is driven, the gear 3a rotates and the spring 4
The rotary member 5 is driven through. The film disc'! is fixed by the winding stop lever 8, which is provided to fit between the films of the film disc. C. Since the rotation is stopped, the charge spring 4 is charged, and the motor 1 is stopped by a torque detection mechanism (not shown), completing preparation for photographing. Photographing is performed together with the shutter release, and the feed stop lever 8 is deactivated and moves in the direction shown by arrow E in the figure, and the stoppage of rotation of the film disc is released. Through a retaining member 6 provided on the film disc that engages with the rotating member 5, the film disc 7 is instantly moved so that the stopper lever 8 fits into the groove between the films due to the driving force of the charged spring 4. As the film is rotated to a position where it does not match, the feed stop lever 8 becomes activated and is stopped by the lower surface of the film in the figure.

Along with the operation of the stop lever 8, the motor 1 is driven, and the film disc 7 is rotated by the driving force of the motor 1, and the stop lever is fitted into the groove 7a between the next film, and one frame is finished. , it is possible to shoot one frame.

In this way, when using a conventional motor that utilizes electromagnetic force, a gear train for reduction is required to convert high rotation and low torque to low rotation and high torque, which increases the number of parts and costs due to this. As the installation space increases, the noise generated by the motor and gear train must also increase.

Here, before moving on to a detailed explanation of the present invention, the principle of an ultrasonic motor and the embodiments thereof that have already been proposed will be discussed. Figure 2 is a diagram of the principle of a surface wave type ultrasonic motor. When vibration is applied to the surface of the elastic body 11 using an electrostrictive element, a surface wave is generated and propagates on the surface of the elastic body. now,
If the traveling direction of this surface wave is the direction of arrow A, the movement of the mass point near the surface of the elastic body 11 is counterclockwise as shown by arrow A.
Since the moving object 10 is rotating in the opposite direction, when the moving object 10 is brought into pressure contact with the moving object 10, the moving object 10 moves in the direction of the arrow B.

Figure 3 shows a practical array of a surface wave type ultrasonic motor made in an annular shape, in which a ring-shaped electrostrictive element 12 made of ceramic or the like is used to apply vibration to an elastic ring llb to generate a surface wave. , This is used to rotate the rotor (moving body) 10b. The rotor 10b may be annular or disc-shaped.

Note that as a method for generating a surface wave, a traveling wave in one direction can be generated by forming interdigital electrodes on the surface of the electrostrictive element 12 and applying high frequency voltages with a phase shift to each electrode. Also, by reversing the phase, the rotor 10b
It is also possible to reverse the direction of rotation.

FIG. 4 shows an example in which a surface wave type ultrasonic motor is used in an automatic film feeding device of a camera using disc film. In the figure, the elastic ring llb has
An electrostrictive element 12 to which an electrode 14 is attached is attached, and a surface wave generated by the electrostrictive element 12 rotates a disc-shaped rotor 10c. A shaft 13 is fixed at the center of rotation of the rotor 10c, and drives the rotating member 3C. The above member 10c
, llb, 12 constitute an ultrasonic motor.

17 is a drive power supply for the ultrasonic motor, and is a monostable multi-? (via the analog switch 16 controlled by the output of the ibrator 18,
9 connected to the other electrode set 14b through 5
The 0° phase shifter 15 rotates the rotor IQc in one direction.
In other words, rotation of the film feed is provided.

The winding stopper lever 8a closes the groove 7a of the disc film during photographing due to the biasing force of a spring 32 fixed by the camera body.
It is mated with The electromagnet 30 is arranged close to the winding stop lever 8a, and is controlled by a shutter travel detection circuit 31.

In addition, the same components as the conventional example in FIG. 1 are given the same reference numerals.
The explanation will be omitted.

The operation will be described below with reference to the timing chart shown in FIG. The shutter running detection circuit 31 detects the end of shooting one frame of film, and the electromagnet 30 is energized for a time TI (C time tI) (FIG. 5A), and the winding lever 8a is pulled in the direction of arrow F in the figure, and the disc film is 7 is disengaged from the groove 7a. The pre-charged charge spring 4 instantaneously rotates the film disc 7 to a position where the groove 7a is not engaged with the stopper lever 8a.

When the electromagnet 30 is de-energized, the monostable multi-noise oscillator 18 outputs rHiJ pulses for a time T (FIG. 5B), opens the gate of the analog switch 16, and the ultrasonic motor is driven. The time T is set to a value necessary for rotating one frame of the disc film.

In the figure, at time T, the film is stopped and /<-82 is fitted with the next film groove, the disk film is stopped rotating, and the ultrasonic motor is activated a little later, at time 1. The drive is stopped at , and the charge spring 4 is charged. In this way, the film is automatically advanced one frame at a time.

Although the rotor 10G and the rotating member 3C are provided independently for convenience, it is clear that the rotating member 3C may be used directly as the rotor 10c, which further reduces the number of space components.

In the above example, a film stopper of 88N/(N32, etc.) was used, and a mechanical restriction was applied as a film stopper. , a simpler embodiment is shown in FIG.

In the figure, the block indicated by a broken line is a photocoupler, which is arranged so that the groove position of the disc film can be read photoelectrically. 20-a is a photodiode, and 20-b is a phototransistor, which are fixed to the camera body.

Reference numeral 21 indicates that the photodiode control transistor 22 is a pace resistor, the resistor 23 is a monostable multi-node oscillator, the resistor 23 is a load resistor, and the output 0 opens and closes the analog switch 16.

The operation will be explained below.

At the same time as the shooting of one frame of film is completed, the monostable multistable is triggered in the shutter running detection circuit 31 similar to that shown in FIG. 4, and a "Hi J" level output is applied to the base of the transistor 21 for one hour. The transistor 21 becomes oFF, no current is supplied to the photodiode 20-a, the output (2) becomes the "Hl" level, and the gate of the analog switch 16 is opened.

The ultrasonic motor drive power source 17 passes through the electrode group 14-a and the 90° phase shifter 15, and then passes through the electrode group 14-b.
Drives the motor and rotates the film disc.

The time T is set so that the film disc is rotated to a position where the groove 7a of the film disc is removed from the communication path of the photocoupler.

When the base potential of the transistor 21 reaches the rLo level, a current is supplied to the photodiode 20-a, but since the communication path of the photocoupler 20 is cut off by the film 7, the transistor 20-b remains in the oFF state. Yes, the output Vo remains at the rHiJ level and the ultrasonic motor continues to be driven. When the film disk 7 rotates and the next film groove comes to the communication path of the photocoupler, the transistor 20-b turns on and the output 9 becomes rLo.
When the level reaches J level, the gate of the analog switch 16 is closed, and the ultrasonic motor is instantly stopped and fixed (held) by the friction between the elastic body 11b and the rotor 10c, and the preparation for photographing is completed. In this way, one frame of film is automatically fed, making it possible to provide a completely noiseless and more compact mechanism.

(Effects of the Invention) As described above, according to the present invention, since it is possible to create a disk-shaped motor with a small thickness, there is not only a great advantage in terms of space when incorporating it into a disk camera using a disk film. , without using a gear train for reduction,
Since the film disc can be driven, not only is it possible to significantly reduce the number of parts, but the noise emitted by the motor and gear train, which is undesirable for use, is virtually eliminated, greatly improving the usability. It will be measured.

Furthermore, since the motor itself is structurally simpler than the conventional electromagnetic type, it is possible to reduce the number of parts and reduce costs9. In order to feed accurately, the winding stop lever 8,
Although the charging spring 4 and the like are used, it is possible to control the angle of the moving body 10c by controlling the energization time of the electrostrictive element 12, etc. In this case, the moving body 10c is directly engaged with the film disk. By using a coupling member, the winding stopper lever 8, which requires mechanical positioning accuracy, is omitted, and the charge spring 4 is also unnecessary, allowing for further compactness.

[Brief explanation of drawings]

Figure 1 is a diagram of an automatic film feeder for a camera using conventional disc film. Figure 2 is a diagram of the principle of a dual-wave ultrasonic motor.
Embodiment of a surface wave type ultrasonic motor FIG. 4 shows an example of the present invention in which a surface wave type ultrasonic motor is incorporated into a disk film feeding device. FIG. 5 is a diagram for explaining the operation of the above embodiment. , timing diagram FIG. 6 shows a second embodiment using photoelectric reading means. (Explanation of symbols of main parts)

Claims (1)

[Scope of Claims] A pressurized liquid comprising an electrostrictive element, an elastic body on whose surface a surface wave is generated by the electrostrictive element, and a nuclear elastic body. The ultrasonic motor is equipped with an ultrasonic motor constituted by a rotatable force rotor, and is mechanically coupled so that the center of rotation of the core rotor coincides with the center of rotation of a film winding engagement member provided on the film disk. An automatic film feed device for a disc camera, characterized in that the film disc is rotated by the rotation of the rotor.