JPH01269577A - Silencer for impact dot printer - Google Patents

Abstract

PURPOSE:To reduce noises with printing without scaling up and weighting printer itself by emitting a sound having polarity reverse to noises from a sounding means while being synchronized with noises generated by printing. CONSTITUTION:A corresponding acoustic signal is prepared on the basis of a control signal and acoustic data 20 stored in a memory 14 by interruption operation according to the program of sound-arresting operation by a CPU 13, and outputs to an acoustic-signal output port 21 at specified timing, and a speaker 24 mounted into a printer through a D/A converter 22 and an amplifier 23 is driven. The acoustic data 20 represent coded data in which generated sounds are collected at every character, at every printing wire or at every combination of the printing wires. A sound generated from the speaker 24 forms a waveform having polarity reverse to a printing sound generated by driving a wire on the basis of a signal prepared by these data, and functions as nullifying the printing sound.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a silencer for an impact dot printer.

[Conventional technology]

Impact dot printers are widely used as output devices for combination printers, etc., but their printing method uses a wire stylus, ball, etc. as a printing member to hit the paper (thereby printing is done). This generates a considerable amount of printing noise.Therefore, printer cases have traditionally been reinforced to increase their rigidity, and the case material has been made heavier (and thicker).
Sound-absorbing materials, sound-insulating materials, vibration-proofing materials, etc. were used, and gaps were eliminated to prevent the generated noise from escaping the cover as much as possible. In some cases, the entire printer was placed inside a soundproof box.

[Problem to be solved by the invention]

However, according to the above-mentioned measures, there is a problem that the printer itself becomes larger and heavier, which impairs operability.

The present invention solves the above-mentioned problems, and aims to provide a noise reduction device for a printer that can effectively reduce noise associated with printing without increasing the size and weight of the printer itself.

[Means to solve the problem]

According to the present invention, this purpose is achieved by using a sound generating means built into the impact dot printer, a storage means for storing acoustic data for canceling the printing sound, and a signal for controlling the drive of the member that performs printing impact. an acoustic signal generating means for reading acoustic data from the storage means and creating a corresponding acoustic signal based on the above, and the output of the acoustic signal generating means drives the sounding means to erase the print sound. This is achieved by providing a noise damping device featuring impact dot printing.

[Effect]

According to this structure, since a sound of the opposite polarity to the noise generated by printing is emitted from the sounding means in synchronization with the noise generated by printing, the noise is canceled and printing can be performed without using a large amount of soundproofing material. Erase effectively.

〔Example〕

Preferred embodiments of the invention will now be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram showing the functional configuration of a silencer for an impact dot printer based on the present invention.

The print signal 11 from the computer etc. is input to the input board 12
is input.

The CPU 13 outputs the print signal 1 according to the print program.
1, the character data 19 (control data for printing characters, etc.) stored in the memory 14 is called, and based on this, a control signal is given to the parallel output boat 15 and the timing signal output boat 16 to control the printing wire drive coil. 17 is selectively energized at the required timing, and at the same time, the motor drive circuit 1 of the step motor for carriage feeding is activated by the output from the timing signal output boat 16.
8 and prints characters, figures, etc.

At this time, the CPU 16 creates a corresponding acoustic signal based on the control signal and the acoustic data 20 stored in the memory 14 by an interrupt operation according to the program of the muting operation, and outputs it to the acoustic signal output port 21 at a predetermined timing. D/A
A speaker 24 installed inside the printer is driven via a converter 22 and an amplifier 26. Acoustic data 20
is coded data in which the generated sounds are recorded for each character, each printing wire, or each combination of printing wires. The sound generated by the speaker 240 forms a waveform having a polarity opposite to that of the printing sound generated by the wire drive, based on the signal created from these data, and serves to cancel out the printing sound. There is a predetermined time delay from the generation of the control signal to drive the printing wire to the generation of the printing sound, but the program is designed so that the erase sound is generated from the speaker in accordance with this time. The tires can be assembled together, or the tires can be adjusted using an external operating member.Also, by adjusting the gain of the amplifier 26, the peak value of the speaker output can be adjusted to accurately (cancel out) the printing sound. You can also do that.

Furthermore, although FIG. 1 shows a case where the CPU 13 is used for both printing and muting purposes, and the memory 14 is also used for character data 19 and audio data, in the present invention, the muting device is In order to improve the functionality, the device can be configured such that these are independent for each purpose of printing and sound deadening.

FIG. 2 is a flowchart showing the flow of a program in the silencer shown in FIG.

The process starts when the silencer is switched on, and when a printed signal is detected at Sl, a control signal is generated at 82.Based on this signal, acoustic data is read at S3, and an acoustic signal is created based on the acoustic data and the control signal at S4. However, in S5, S2
An acoustic signal is output when a predetermined timing elapses.

FIGS. 3(a) to 3(e) show the mechanical structural arrangement of the silencing device according to the present invention. Printer 600 is case 3
A platen 602, a carriage 303 that slides along the platen 602, and a print head 304 mounted on the carriage 303 are housed in the 01, and paper (not shown) is stored through a window 305.
The paper is sandwiched between the platen 302 and the print head 604, and the paper is sent by the rotation of the platen 602 to the print head, and characters, figures, etc. are printed on the paper by the impact of the printing wire 606 provided in the print head 304. Print out. "Print head"
304 is a permanent magnet at 5 as shown in Figure 3 (Q).

307-1, a yoke 307-2, an iron 307-3, an electromagnet 307 consisting of a drive coil 307-4, and an armature 310 driven by the electromagnet 307, supported by a leaf spring 608, and having a printing wire 306 fixed to its end. Multiple sets are provided, and the printing wire 6 is activated by energizing the drive coil 307-4.
06 to the guide member 311 (311-1 and 311-2
) and is impulsively driven toward the platen 602 to perform printing on the paper via the ink ribbon 612. A sound deadening container 316 that surrounds a portion of the print head 304 and platen 302 is attached to the carriage 606, and a speaker 315 is mounted opposite to the through hole 314 of the sound deadening container.
is obsessed. Most of the noise generated by printing is -
The sound is taken into the sound-absorbing container 313, reflected on the wall surface, and becomes a standing wave. Since the phase relationship of the waveform is the same everywhere in the container, it is easy to cancel this with the sound generated from the speaker.

FIG. 4 shows the arrangement of speakers in another embodiment of the invention. A speaker 315 is attached to the case 301 and emits sound into the case, and the print head 304,
The same silencing effect as in the embodiment shown in FIG. 3 is performed on the sound generated by the platen 302.

FIG. 5 is a block diagram showing the functional configuration of another embodiment of the present invention. The configuration is that a microphone 51, an amplifier 53, and an A/D converter 52 are added to the embodiment shown in FIG. The microphone 51 detects the overlapped sound of the printing sound and the sound generated by the speaker 24,
The detected sound data is input to the input port via the A/D converter 52, and the magnitude of the sound signal is controlled according to a program described later. Other operations are similar to the embodiment shown in FIG.

FIG. 6(a) is a flow chart showing the flow of a program in the silencer shown in FIG. 8 from the start
The steps up to step 4, the creation of the acoustic signal, are the same as in the flowchart of FIG. 84 to modify the acoustic signal at S25.
The data of the acoustic signal (this is designated as S) is multiplied by a coefficient K to obtain S-, and the modified signal is calculated as the second signal at 826.
It appears at a predetermined timing similar to the flowchart in the figure.

At 827, a synthesized sound of the speaker sound generated by the output and the printing sound generated separately from this is recorded with a microphone, and this is recorded by the A.
Detection data obtained by /D conversion is input, and sampled at 828 to output sampling data SD. In S29, the sampling data SD and the internally set data ID are compared, and in the case of 5D) ID, a constant is added to the coefficient K in S29 to make it K again, and if SD≦ID, the coefficient is changed. Instead, the data of K is stored in a register or the like at 831 and used for the next signal correction. In this way, each time a print signal is received from the outside, the steps are repeated and K can be successively corrected to an appropriate value. At the beginning of the first half, if you set K to a value smaller than the appropriate value and set the ID and - to a sufficiently small value, the learning function will automatically set the coefficient K with the highest silencing effect. After that, printing continues in the ideal muted state.

FIG. 6(b) is a flowchart showing the flow of another program in the silencer shown in FIG.

The steps up to 828 are the same as those in FIG. 6(b), and the illustration up to 827 is omitted. In S39, the n-th sampling data SD and the previous sampling data 5D1
Compare the absolute value of 1-1, and if it increases, 84
Invert the sign of 1 at 0, and if it does not increase, leave it as is and change to = +K at 841.

Correct K by the calculation. In this case as well, learning automatically maintains K within an appropriate range, achieving ideal muffling.

〔Effect of the invention〕

As described above, according to the present invention, the printing sound in an impact dot printer can be canceled out or almost canceled out by the sound having the opposite polarity, so that the printing sound can be canceled out more effectively than in the case of using a sound insulating member or a soundproofing member. It can be erased and the required space can be reduced, which is a great advantage.

[Brief explanation of the drawing]

1 and 5 are block diagrams showing the functional configuration of a silencer for an impact dot printer based on one embodiment and another embodiment of the present invention, respectively, and FIG. Flowcharts showing the flow of the program in the example, FIGS. 3 and 4 show the mechanism and arrangement of the silencer of the present invention, FIGS. 3(a) and 3(b) are perspective views, and FIG.
) is a partial sectional view, FIG. 3(d) is a partially cutaway side view, FIG. 3(e) is a plan view, FIG. 4 is a partial sectional view of a speaker in another embodiment of the present invention, and FIG. Figure (a), Figure 6 (
b) is a flowchart showing the flow of the program in the embodiment shown in FIG. 12...Input boat, 13...C
P.U. 14...Memory, 15...Parallel output boat, 16...Timing signal output boat, 17.307-4...Print wire drive coil, 19. ...Character data, 20...
...Acoustic data, 21...Acoustic output boat, 24.615...Speaker, 300...
...Printer 1, 601... Case, 302.
...Platen, 306...Carriage, 604...Print head, 606...Print wire, 311...Guide. 612... Ink ribbon, 613... Sound deadening container, 51... Microphone, 26.56... Amplifier, 22... D /A converter, 52...A/D converter. ``LLI Δ-S @ Figure 3 (a) Figure 3 (C) (d) Figure 4 Figure 6 (a) Figure 6 (b)

Claims (3)

[Claims] (1) A sound generating means built into the impact dot printer, a storage means for storing acoustic data for canceling the printing sound, and a sound generating means from the storage means based on a signal for controlling the drive of a member that performs printing impact. an acoustic signal generating means for reading data and generating an acoustic signal for canceling printing noise, and the sounding means is driven by the acoustic signal to attenuate printing noise. . (2) The impact dot printer includes a built-in microphone and an A/D converter that converts the output of the microphone into digital data, and an acoustic signal is generated by an acoustic signal generating means based on the output of the A/D converter. 2. The noise reduction device for an impact dot printer according to claim 1, wherein the noise reduction device performs the correction. (3) The sound deadening device for an impact dot printer according to claim 1, wherein the sound generating means is mounted on a sliding carriage carrying the print head, and is attached to a container surrounding the print head.