JPH05155104A - Printer - Google Patents

Abstract

PURPOSE:To prevent producing of printing noises in impact printing by a method wherein a control device that outputs sound in the same volume and in an opposite phase as sound produced by a recording head is provided to a sound- producing means that moves together with the recording head. CONSTITUTION:Head driving signals generated in accordance with image data to be printed are temporarily stored in a buffer 21. With the data transferred from the buffer 21, a driver 22 drives a recording head 15 to operate printing work, and such working parts execute printing works on the head driving signals. A control circuit 23 that controls operation of a speaker S is constructed of an inverted printing sound-producing circuit 23a that produces sound in the same loudness with and in an opposite phase to printing sound produced by the recording head, and a driver 23b that drives the speaker S. Therefore, sounds produced by hammers are offset by the sound produced from the speaker, S, and ambience surrounding the printer can be kept quiet.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording printer, and more particularly to a printer which suppresses the generation of sound during a printing operation.

[0002]

2. Description of the Related Art With the recent development and popularization of OA equipment,
Printers are used as accessories for office computers and word processors in each office. There are various printing methods for such a printer, and an example of the structure of a printer head that employs a hammer striking method is shown in FIG.

This recording head faces a front yoke 1 and a rear yoke 2 for forming an electromagnetic circuit, a permanent magnet 3 attached and fixed to one end of these yokes 1 and 2, and a permanent magnet 3. Between the core 4 fixed to the rear yoke 2 at a position, the electromagnetic coil 5 wound around the core 4 and electrically connected to the control circuit and the drive circuit, and the front yoke 1 and the permanent magnet 3. It is composed of a leaf spring 6 sandwiched and a printing pin 7 as a recording element which is attached to the tip of the leaf spring 6 and constitutes a hammer for printing together with the leaf spring. The front yoke 1 has a pin through hole 8 at the tip thereof, and the print pin 7 projects forward of the front yoke 1 through the pin through hole 8. Also, the front yoke 1
A second through hole 9 is provided at a portion (lower side position in FIG. 6) of the pin through hole 8 on the proximal end side. A tip 10 is attached to the portion of the leaf spring 6 corresponding to the second through hole 9, and the tip 10 projects forward of the front yoke 1 through the second through hole 9. A plurality of sets of the magnetic members 3, 4, 5, the leaf spring 6, and the printing pin 7 are provided for one recording head (for example, 24 sets).
Sets), and the tips of the print pins 7 for the number of sets face the platen surface.

In such a structure, when no current is conducted to the electromagnetic coil 5, the leaf spring 6 is attracted to the core 4 by the magnetic action of the permanent magnet 3. In this case, the leaf spring 6
The gap between the front yoke 1 and the front yoke 1 is filled with the chip 10, and the magnetic flux density of the permanent magnet 3 does not decrease and reaches the rear yoke 2 from the front yoke 1 through the core 4.

On the other hand, when a timing pulse for a print command is output from the control circuit and the drive circuit operates, a current is passed through the electromagnetic coil 5 in a direction to cancel the magnetic flux of the permanent magnet 3. When a current is conducted to the electromagnetic coil 5 and the magnetic flux from the permanent magnet 3 is canceled, the leaf spring 6 becomes free accordingly, and the leaf spring 6 separates from the core 4 by its own repulsive force, and the printing pin 7 prints on the recording paper.

In such a hammer striking type printer, since the printing operation is performed by striking the platen with a hammer, noise is generated, and this noise has a drawback that the inside of the office becomes noisy. As one of the measures to eliminate this drawback as much as possible, there is a method of adopting a so-called divided printing method as a printing method. This is to shift the start timing of the print operation for a plurality of print pins at a certain print operation timing. The division printing operation will be described with reference to FIG. 9A shows the encoder output 11 which gives the print operation timing to the recording head.
When the encoder output 11 is applied to the recording head, the plurality of print pins 7 start the printing operation, but in divided printing, as shown in (b) of FIG. The print pulse 12 is applied with a time interval of time τ, and the printing operation starts in the order in which the print pulse 12 is applied. As a result, in the case of division printing, as an example, the frequency is 109.35 kHz and the volume level is L.
Print noise of high frequency and low level is generated.
Therefore, compared to the level L of the print sound when a plurality of recording heads simultaneously enter the printing operation by the encoder output 11 as shown in (c) of FIG. ) Or (e), the level of the printing sound becomes Lo, and the volume can be reduced to some extent.

[0007]

However, even if such a printing method by division printing is adopted, it is not possible to completely suppress the generation of printing noise. Moreover, when divided printing is performed, not all the printing pins 7 perform printing operation for one encoder output 11, and therefore, as shown in (d) of FIG.
Occurs. Due to the occurrence of this printing omission 13,
As shown in (e) of FIG. 9, there was a problem that a beat noise of about 4 kHz was generated.

The present invention has been made in view of the above problems, and an object thereof is to provide a printer capable of suppressing the generation of noise even when printing is performed by a striking method using a hammer or the like.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a printer with voice generating means and control means for causing the voice generating means to generate voice at a predetermined timing. And

[0010]

In the printing operation of the printer, printing is performed by the hammering operation of the hammer. The control means detects the striking motion by the hammer and operates the sound generating means with a delay of a certain time from the striking motion. Since the voice generation means generate various voices from high to low,
A plurality of them are provided to generate and output a sound having a phase opposite to that of a sound generated by a driving mechanism such as a hammer or a motor, or a hammer. As a result, the sound generated from the hammer or the like and the sound output from the sound generating means cancel each other out, and the surroundings of the printer are kept quiet.

[0011]

1 and 2 are views showing the mechanical construction of a printer according to the present invention. Of these, FIG. 1 is a perspective view of the printer. In this figure, reference numeral 11 is a printer main body, 12 is a key for inputting various operation instructions to the printer, and 13 is an opening through which recording paper is inserted and ejected. FIG. 2 schematically shows the internal structure of this printer. Inside the printer, a speaker 14 as a sound generating means, a recording head 15 similar to that shown in FIG. 5, and this recording head 15 are shown. And a platen 16 installed to face each other. A speaker 17 is provided near the recording head 15 and the platen 16 in addition to the speaker 14. The speaker 14 includes a motor portion of the printer and a platen 16
Sound with relatively few frequencies generated from the operating parts of
That is, a speaker that emits a low tone is used so as to match the low tone, while a speaker that emits a high tone is used as the speaker 17 so as to match a relatively high frequency sound generated during the printing operation of the recording head 15, that is, a high tone. .. The high-pitched speaker 17 is placed on the recording head 15, and even if the position changes due to the movement of the recording head 15 in the main scanning direction, it is possible to always emit sound from the position of the recording head 15. There is.

FIG. 3 is a diagram showing a basic circuit configuration example of the printer of the present invention. In this figure, reference numeral 21 is a buffer for temporarily storing a head drive signal generated based on image data to be printed, and 22 is a buffer 2.
1 is a driver for receiving a data transfer from the print head 15 to perform a print operation, and these operating parts execute a print processing operation by a head drive signal. As the head drive signal, image data for one line or image data for one line divided into a predetermined group is input as print data. Reference numeral 23 is a control circuit for controlling the operation of the speaker S. This control circuit 23 generates a reverse print sound that generates a sound of the same magnitude in a phase opposite to the print sound of the recording head based on the head drive timing signal a. It is composed of a circuit 23a and a driver 23b for operating the speaker S. As the speaker S, the bass speaker 14 and the treble speaker 17 shown in FIG. 2 correspond.

FIG. 4 is a diagram showing a first embodiment of the control circuit 23. The control circuit 23 according to this embodiment is used to control the sound erasing in the recording head 15 of the type that performs simultaneous printing on a plurality of printing pins 7. In this embodiment, the control circuit 23 is roughly divided into a treble control section that controls the operation of the treble speaker 17 and a bass control section that controls the operation of the bass speaker 14. The common part of the high-pitched sound control unit and the low-pitched sound control unit is connected to the output side of the buffer 21, and the OR gate 26 that takes the logical sum of the outputs of the buffer 21 and the delay circuit 24 that delays the transfer time of the output data of the OR gate 26. Composed of and. Further, the treble control unit shapes the waveform of the output signal of the delay circuit 24.
A filter 27, a signal inverting circuit 28 that inverts the filter output, and a gain circuit 2 that amplifies the inverted signal.
9 and a driver 30 for driving the high-pitched speaker 17. The bass controller drives the filter 31 that shapes the waveform of the output signal of the delay circuit 24, the signal inverting circuit 32 that inverts the filter output, the gain circuit 33 that amplifies the inverted signal, and the bass speaker 14. And a driver 34.

Further, in this printer, the counting circuit 35 for detecting the number of dot data to be printed in the head drive signal from the output of the buffer 21.
And a delay circuit 36 for time-adjusting the output of the counting circuit 35.
And a D / A conversion circuit 37 for converting a digital signal into an analog signal and inputting it to the gain circuits 29 and 33. The head drive timing signal a is supplied to the counting circuit 35.
Is entered. The head drive timing signal a is also input to the buffer 21.

The operation of the printer according to the first embodiment will be described below. In the printing operation, when the head drive signal is input to the buffer 21 in synchronization with the head drive timing signal a, this signal is transferred to the driver 22 to drive the recording head 15 to perform printing. This operation causes the printer to generate a print sound.

This printing sound is shown in FIG. 5 (a).
As is clear from this figure, the printed sound is the high-pitched area component A
And the bass region component B are included. The delay circuit 24 takes in the logical sum output of the head drive signals output from the buffer 21, and the time from the recording operation of the recording head 15 until the actual print sound is generated and the speaker 1
4 and 17 are synchronized with the time when the voice is emitted. The output of the delay circuit 24 is branched and input to the filters 27 and 31 so as to be divided into a high-pitched sound control unit and a low-pitched sound control unit, and filtered by the filters 27 and 31, respectively, and converted into a high-pitched sound signal and a low-pitched sound signal. After that, it is input to the inversion circuits 28 and 32.

The inversion circuits 28 and 32 perform signal inversion processing so that the speaker output has an opposite phase with respect to the print sound. The inverted signal is amplified by the gain circuits 29 and 33, passes through the drivers 30 and 34, and the treble speaker 1
7. The sound is input to each of the bass speakers 14 and sounds are emitted. In parallel with this voice generation operation, the buffer 2
The output of 1 is also input to the counting circuit 35. Counting circuit 35
A head drive signal is also input to the device, and the number of data to be printed is included in the head drive signal transferred at each timing. The output of the counting circuit is input to the delay circuit 36, whereby the timing of the print sound generation time and the timing of the sound generation of the speakers 14 and 17 are adjusted.

The output signal of the delay circuit 36 is D / A converted by the D / A conversion circuit 37, and then the gain circuit 2
It is input to 9 and 33 as a gain control signal.
As a result, when the head drive signal contains a large amount of data to be printed, a large amplification factor is input to the gain circuits 29 and 33. On the other hand, when the data to be printed included in the head drive signal is small, a small amplification factor is input to the gain circuits 29 and 33. As a result, the high-pitched sound speaker 17 outputs a voice having a phase opposite to that of the high-pitched sound component A of the print sound and having the same volume as shown in FIG.
As shown in (c), a voice having a phase opposite to that of the low tone component B of the print sound and having the same volume is emitted. Especially for high frequencies
The peaker 17 is placed on the recording head 15 and moves as the recording head 15 moves in the main scanning direction.
A sound of opposite phase can always be emitted from the position of the recording head 15, and the silencing effect is great. These speakers 14, 1
The voice generated from 7 is synthesized with the actual print sound.
As a result, the synthesized sound becomes almost 0 as shown in FIG.

FIG. 6 is a second circuit diagram of the control circuit 23 shown in FIG.
It is a figure which shows the Example of. Control circuit 2 according to this embodiment
Reference numeral 3 is used to control sound erasing in the recording head 15 of the type that performs divided printing on the plurality of printing pins 7. Also in this embodiment, the control circuit 23 is divided into a high-pitched sound control unit and a low-pitched sound control unit, as in the first embodiment. The common part of the high-pitched sound control unit and the low-pitched sound control unit is connected to the output side of the buffer 21 and takes in the head drive signal to be transferred and delays the transfer time of this head drive signal.
4 and a differentiating circuit 25 for differentiating the output of the delay circuit 24.
OR gate 26 which takes the logical sum of the output of the buffer 21 and
Composed of and. Also, the high-pitched sound control unit and the low-pitched sound control unit are
Each has the same configuration as that of the first embodiment.

The operation of the printer according to the second embodiment will be described below. In the printing operation, when the head drive signal is input to the buffer 21 in synchronization with the head drive timing signal a, this signal is transferred to the driver 22 to drive the recording head 15 to perform printing. Since the head drive signal is input and transferred separately for each print pin 7, in the recording head 15,
The print pin 7 operates with a certain timing shift to perform divided printing. This operation causes the printer to generate a print sound.

The waveform of this printing sound is shown in FIG. 7 (a). This figure has the same waveform as that of FIG. 9 (e) described above. The delay circuit 24 takes in the head drive signal output from the buffer 21, and the time from the recording operation of the recording head 15 until the actual print sound is generated and the time at which the speakers 14 and 17 emit a sound. Adjust the timing of. The signal pulsed by the differentiating circuit 25 is input to the OR gate 26, where it is checked whether or not there is data to be printed in the head drive signal. If there is even one piece of data to be printed, the output of the OR gate 26 is turned on and the speakers 14 and 17 are driven.

The output of the OR gate 26 is branched and input to filters 27 and 31 so as to be divided into a high tone control section and a low tone control section, and filtered by the filters 27 and 31, respectively, and converted into a high tone sound signal and a low tone sound signal. Then, it is input to the inverting circuits 28 and 32. The inversion circuits 28 and 32 perform signal inversion processing so that the speaker output has the opposite phase to the print sound. The inverted signals are amplified by the gain circuits 29 and 33. At this time, when the head drive signal includes a large amount of data to be printed, a large amplification factor is input to the gain circuits 29 and 33. On the other hand, when the data to be printed included in the head drive signal is small, a small amplification factor is input to the gain circuits 29 and 33. Then, the amplified inverted print sound signal is input to the high-pitched speaker 17 and the low-pitched speaker 14 via the drivers 30 and 34, and a voice is emitted. As a result, from the high-pitched sound speaker 17 and the low-pitched sound speaker 14, a voice having a phase opposite to that of the print sound and having the same volume as shown in FIG. 7B is emitted. In particular, the treble speaker 17 is placed on the recording head 15,
Since the recording head 15 moves together with it when it moves in the main scanning direction, it is possible to always emit a sound in an opposite phase from the position of the recording head 15, and a great silencing effect. These voices emitted from the speakers 14 and 17 are combined with the actual print sound. As a result, the synthesized sound becomes almost 0 as shown in FIG.

In the above description, the high-pitched speaker 17 and the low-pitched speaker 14 are separately prepared as the loudspeaker S that emits the reverse printing sound, and the high-pitched speaker 17 is placed on the recording head 15 while the low-pitched tone is placed. Although the speaker 14 for use is attached to the printer body, unlike this, the speaker for high-pitched sound and the speaker for low-pitched sound may be integrated and the integrated speaker may be attached to the recording head 15.

As described above, according to the present invention, the voice generating means mounted on the recording head of the printer and the means for controlling the operation of the voice generating means are provided, and the control means is the voice. Since the generating means generates a sound having a phase opposite to that of the printing sound and having the same volume, an extremely quiet environment can be maintained even during the printing operation.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing an external structure of a printer according to the present invention.

FIG. 2 is a side view schematically showing the inside of the housing of the printer.

FIG. 3 is a diagram showing a basic circuit configuration example of the printer.

FIG. 4 is a block diagram showing a first embodiment of a speaker control circuit of the printer.

5A and 5B are waveform charts for explaining the speaker drive control operation in the first embodiment, wherein FIG. 5A is a waveform chart of a print sound generated during a print operation, and FIG. 5B is a waveform showing a sound generated by the high-pitched speaker. FIG. 6 (c) is a waveform diagram showing a sound generated by a low-pitched speaker, and (b) is a waveform diagram showing a synthesized sound of a sound generated by a high-pitched speaker and a low-pitched speaker and a print sound.

FIG. 6 is a block diagram showing a second embodiment of the speaker control circuit of the printer.

7A and 7B are waveform charts for explaining the speaker drive control operation in the above-described embodiment, including (a) a waveform chart of a print sound generated during a printing operation, and (b) a sound generated from a high-pitched speaker and a low-pitched speaker. FIG. 4C is a waveform diagram showing a synthesized sound of a sound generated by a high-pitched speaker and a low-pitched speaker and a print sound.

FIG. 8 is a side sectional view showing an example of a recording head adopted in a printer to which the present invention is applied.

FIG. 9 is a diagram illustrating a processing operation for suppressing print noise in a conventional printer, including (a) an encoder output that gives a print operation timing to a recording head, and (b) printing applied to each print pin of the recording head. Pulse (c) Waveform diagram of the printing sound generated during the printing operation in simultaneous printing, (d) Waveform diagram of the printing sound generated during the printing operation in divided printing, (e) Printing generated during the printing operation in divided printing It is a figure which models and shows the waveform chart of sound.

[Explanation of symbols]

 14 high-tone speaker 15 recording head 16 platen 17 low-tone speaker 21 buffer 22 driver 23 control circuit (control means) 24 delay circuit 27, 31 filter 28, 32 inverting circuit 29, 33 gain circuit 35 counting circuit 36 delay circuit 37 D / A conversion circuit

Claims (5)

[Claims] 1. A recording head for recording by a striking operation, a platen provided so as to face the recording head, and a drive mechanism for reciprocating the recording head along the platen.
A printer having a housing for accommodating these actuating members comprises a sound generating means mounted on a recording head and moving together with the recording head, and a control means for transmitting a sound signal to the sound generating means. A printer characterized in that the sound generating means outputs a sound having a phase opposite to that of the printing sound of the recording head and having the same volume. 2. A sound generating means other than the sound generating means mounted on the recording head is attached to the housing,
2. The printer according to claim 1, wherein the sound generating means mounted on the recording head comprises a high-pitched speaker, while the sound generating means mounted on the housing comprises a low-pitched speaker. 3. The printer according to claim 1, wherein both the high-pitched speaker and the low-pitched speaker are incorporated in the sound generating means mounted on the recording head. 4. The printer according to claim 1, wherein a sound generating unit is provided for each sound source of the printer, in addition to the sound generating unit mounted on the recording head. 5. A recording head for printing on recording paper, a buffer to which print data corresponding to a plurality of print pins assembled to this recording head are simultaneously input, and a print head output by the buffer A printer having a driver for driving the printer.