JPS6235075Y2 - - Google Patents

Description

[Detailed description of the invention] This invention uses a sounding body for the self-timer device of a camera, especially the operation display element of the self-timer.
This invention relates to a self-timer device that changes its volume in accordance with the distance setting operation of a lens, for example, the setting position of a distance ring.

Various types of cameras are already known that use a sounding body to indicate the operation of the camera's self-timer and notify the user with a sound that the self-timer is operating, but in all of them, the volume emitted from the sounding body is constant. As the distance between the camera and the subject (user) increases, it tends to become difficult to hear the sound from the sounding body. Also, if you take this into account and configure the volume so that it can be heard even when the distance to the subject is large, there is a risk that it will not only disturb others around the camera, but also cause the user to attract attention from others. , there is also the problem that it is difficult to take natural photographs.

Therefore, as a countermeasure to the above-mentioned problem, a proposal has been made to make it possible to change the volume from the sounding body with a switch, but this is an incomplete countermeasure considering the possibility of forgetting to change the switch.

The present invention was developed in view of the above-mentioned problems, and its purpose is to use a camera configured to adjust the focus to the subject position so that the sound volume from the sounding body at the subject position is adjusted to an appropriate level. The purpose of the present invention is to provide a self-timer device.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block circuit diagram showing one embodiment of a circuit to which the present invention is applied. 1 is an oscillator that generates clock pulses. 2 is a frequency divider which inputs the clock pulse from oscillator 1 to the CLK terminal, and outputs different frequency-divided outputs from the Qn and Qm terminals. It is assumed that the frequency division ratio is larger for Qm. 3 is an AND circuit,
A constant voltage source 4 supplies a constant voltage to the variable resistor 5.

The variable terminal of the variable resistor 5 is linked to a distance ring or slider, etc. that focuses the lens (not shown) to the subject position, and when such distance setting means is set to a large distance position, the variable terminal is connected to the ground. The resistance value between the variable terminal and ground becomes large, that is, the voltage at the variable terminal becomes large, and when the distance is set at a short distance, the resistance value between the variable terminal and ground becomes small, that is, the voltage at the variable terminal becomes small. .

Reference numeral 6 denotes an operational amplifier (OP amplifier) having a voltage follower configuration, which applies the voltage from the variable resistor 5 to its non-inverting input terminal (+ input terminal), converts it to a low impedance, and outputs it. 7 is an analog switch, and when the S terminal becomes high level, the A and B terminals are short-circuited, resulting in a so-called switch-on state. 8 is an amplifier having a gain sufficient to drive the sounding body 9. The sounding body 9 is composed of an electro-acoustic transducer such as a piezoelectric buzzer or an electromagnetic speaker.

Next, in the above configuration, the operation shown in FIG.
This will be explained using figures. Figure 2 shows the voltage waveforms applied to the sounding element in Figure 1 and 9. (A) shows the waveform when the distance setting value of the distance setting means such as the distance ring on the lens is small, and (B) shows the waveform when the distance setting value is large. , the vertical direction shows the voltage level and the horizontal direction shows the time.

The clock pulse from oscillator 1 is sent to frequency divider 2.
It is input to the CLK terminal and the result is a frequency-divided output from the Qn and Qm terminals (for example, the output from the Qn terminal is 1KHz,
Let that of the Qm terminal be 1Hz. ) appears. By passing both outputs through an AND circuit 3, a pulse output that is intermittent at 1 KHz for 0.5 seconds, and then a state of zero output for 0.5 seconds appear alternately. Based on this, a self-timer that displays audible "Pitsupitsupitsu..."
The following display sound is generated. In conventional cameras, this volume is constant, but in this invention, in order to change the volume level and obtain the appropriate volume, a constant voltage from a constant voltage source 4 is applied to a variable resistor 5 that is linked to the lens distance (not shown). The voltage at the variable terminal is applied to the non-inverting input terminal of the OP amplifier 6 connected as a follower. Therefore, the voltage at the variable terminal of the variable resistor 5 appears as it is at the output of the OP amplifier 6, and the output is input to the A terminal of the analog switch 7. However, since the output of the AND circuit 3 mentioned above is input to the S terminal of the analog switch 7, the voltage of the OP amplifier 6 switched by the output of the AND circuit 3 appears at the B terminal of the analog switch 7. Therefore, the voltage of the variable resistor 5 that is linked to a distance setting means such as a distance ring of a lens (not shown) changes depending on the distance setting value, and for example,
When the distance is small, the output voltage of the OP amplifier 6 is small, which is switched by the analog switch 7 and input to the amplifier 8. The amplifier 8 amplifies the output to a level sufficient to drive the sounding element 9 (second
Figure A) This is applied to the sounding element 9, and a relatively small pulsed sound with a fundamental frequency of 1KHz is emitted every 0.5 seconds. However, when the setting value of the distance setting means of the lens (not shown) is set to a position where the distance is large, the voltage of the variable resistor 5 is large, and therefore the output voltage of the OP amplifier 6 is also large. Then, in the same way as above, the output of the OP amplifier 6 is switched by the analog switch 7, and the output is amplified by the amplifier 8, and the output from the sounding element 9 is output at a higher level than when the distance setting value is small (Fig. 2B).
to drive. Therefore, it is a relatively loud sound, and a pulsed sound with a fundamental frequency of 1KHz is emitted every 0.5 seconds. In addition, the resistor 5 in the example
constitutes a signal forming circuit, and the amplifier 6 and switch 7 constitute a volume adjustment circuit.

As explained above, in cameras that use sound from a sounding device built into the camera to display the operation of the camera's self-timer, the distance between the camera and the subject is large, so the distance setting operation of the lens is difficult. If the distance setting value determined by the lens distance setting is large, the volume from the sounding body will be increased, and if the distance between the camera objects is small, and the distance setting determined by the distance setting operation of the lens is small, the volume from the sounding body will be increased. It reduces the volume. Therefore, regardless of the distance between the camera and the subject, the self-timer operation can be confirmed at a nearly constant volume for the subject, and since this can be done simply by focusing on the subject, it can be operated in exactly the same way as a conventional camera. is of great practical importance.

[Brief explanation of the drawing]

FIG. 1 is a block circuit diagram showing an embodiment of a circuit to which the present invention is applied, and FIG. 2 is a timing level waveform diagram for explaining the operation of FIG. 1. 1... Oscillator, 2... Frequency divider, 3... AND circuit, 4... Constant voltage source, 5... Variable resistor, 6...
Operational amplifier, 7...analog switch, 8...amplifier, 9...sounding body.

Claims (1)

[Claim for Utility Model Registration] A self-timer operation display device for a camera that audibly indicates the self-timer operation using a sounding body, which is linked to a lens drive mechanism that focuses the lens on the subject position, and adjusts the lens position according to the lens position. A self-timer operation display device for a camera, comprising: a signal forming circuit that forms a signal; and a volume adjusting circuit that adjusts the volume of the sounding body in accordance with a lens position signal from the signal forming circuit.