JPS5825363Y2 - Hikari Beam in Satsouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printing device that uses a light beam and is suitable for printing barcodes on tags and the like.

As shown in Figure 1, tags (product price tags) that can be optically read include "One Piece" and "Size 15-3J."
In addition to product information in regular characters such as , barcode C shows product price and other information as an array of bars.
is printed.

For example, a barcode with tag a may be a combination of a narrow bar and a wide bar corresponding to 1" and 0, or a white bar and a black bar of the same width. ′
There are some that correspond to 1" and 0" and use these in combination.

The applicant has developed a photoelectrostatic printing device suitable for printing such barcodes, especially black and white barcodes,
A separate application was filed.

In this photoelectrostatic recording, the bar code has a narrow bar width, so
It is best to use a laser beam that can be focused into a narrow beam.

However, laser tubes not only have large variations in the initial output intensity, but also undergo large changes over time, with the output decreasing to about 60 yen in two years, for example.

That is, the laser tube is installed so as to output a laser beam of approximately maximum intensity, and is assembled so that the amount of exposure to the recording paper is optimized based on the laser beam intensity.

As a result, the laser light intensity decreases due to aging, resulting in insufficient exposure.

Therefore, it is necessary to use some method to compensate for underexposure development caused by changes in laser light intensity over time.

The present invention improves these points and proposes a light beam printing device that can print clear barcodes by keeping the exposure amount constant regardless of variations in the output of the laser device.

A light beam printing device according to the present invention includes a laser device that outputs a light beam of constant intensity, a modulator that modulates the light beam according to input data, and a light beam that is intermittent on the surface of a recording medium according to the input data. an optical scanning mechanism that scans and records; a detector that detects the intensity of the light beam; and a scanning speed of the light beam based on the output of the detector to maintain a constant exposure amount on the surface of the recording medium. The device is characterized by comprising a control circuit, which will be explained in detail below with reference to the drawings.

2 to 5 show an embodiment of the present invention, and FIG. 2 mainly explains the operating principle of photoelectrostatic recording.

In FIG. 2, 1 is a cylindrical electrode, 2 is an electrostatic latent image forming body formed by coating a photoconductor film on the cylindrical surface of the cylindrical electrode 1, and 3 is the surface of the electrostatic latent image forming body 2. 4 is a sheet of paper on which a barcode is printed, 5 is a tag paper, 5 is a transfer device that transfers a latent image onto the tag paper 4, and 6 is a toner. A developing device which disperses the latent image to make it visible, and 7 a paper feeding mechanism.

The operating principle of photoelectrostatic recording is well known. For example, after the electrostatic latent image forming body 2 is uniformly charged, a light image is irradiated by the light scanning mechanism 3, and the charge on the irradiated area is extinguished (disappeared). Or, conversely, an electrostatic latent image is formed (by generating a charge only in the light-irradiated area), this latent image is made into a visible image by scattering toner in the transfer device 5, and this is fixed by heating etc. do.

Note that the latent image forming body is not limited to a drum shape, but may be a flat plate shape.

Alternatively, the recording paper itself may be coated with a photoconductive material to form an electrostatic latent image directly on the recording paper.

Figure 3 shows an overview of the barcode printing machine of the present invention, and shows 11
is paper that can print barcodes etc. e.g. tag paper, 1
2 is a developing device; 13 is a laser device that generates a laser beam;
14 is a light modulator (light shutter), 15 is a condensing lens, 1
6 is a first optical scanner, 17 is a second optical scanner, 18
is arranged between the laser device 13 and the optical shutter 14, and 19 is a detector for detecting the output intensity of the laser device 13 by receiving the spectrum from the mirror 18, such as a photoelectric converter. It is.

The paper 11 has cutting lines 1 such as perforations for each predetermined size.
1a and a position detection hole 11b are provided, and the bar code is intermittently transferred by a predetermined size in the direction of arrow f by a paper feeding mechanism such as a motor, and each bar is lined up in the same direction as the feeding direction when the paper is stopped. An electrostatic latent image is formed.

The first and second optical scanners 16 and 17 project laser beams toward the paper 11 using rotating or vibrating reflectors, and two-dimensionally scan the paper 11 in the same direction and perpendicular direction to the transport direction. In this embodiment, the first optical scanner 16 scans in the transport direction and in one direction.
The respective rotation or vibration directions are set so that the twisted second optical scanner 17 scans each bar arrangement direction in the perpendicular direction thereof, and the output laser beam of the laser device 13 is incident on the first optical scanner 16. Then, the reflected light is projected onto the surface of the paper 11 via the second optical scanner 17.

FIG. 4 shows the control circuit of the printing device shown in FIG.
1 is a register, and 22 is a read-only memory that stores barcodes! 23 is a scanning circuit, 24 is a driver for the optical shutter 14, 25 is a timing generation circuit, 26 is a paper feed motor, 27 is a motor 26
28 is a paper feed control circuit, 29 is a motor that drives the first optical scanner 16, 30 is its driver, 3
1 is a first optical scanner 1 that rotates the motor 29 by one rotation.
6 is a one-turn clutch, 32 is a first scan control circuit, 33 is a motor that drives the second optical scanner 17,
34 is a driver for the motor 33; 35 is a timing disc that is linked to the rotation of the motor 33; 36 is a timing photoelectric converter; 37 is a second scan control circuit; the first and second scan control circuits 32. 37 is given the detection signal (2) of the photoelectric converter 19 for laser output detection.

The register 21 is filled with data corresponding to a barcode to be printed, for example 3, by an operator using a numeric keypad.
Input 218...etc.

This data becomes information specifying the address of ROM22,
This specifies the address.

The timing generation circuit 25 receives an output pulse from a timing photoelectric converter 36, which is generated by the rotation of a timing disk 35 that is connected to the output shaft of a motor 33 and has a large number of openings 35a at equal intervals around its periphery, and generates a module pulse M.
P1 character pulse CP and 1 tag scan timing pulse STP are generated, one character pulse CP is generated for every 7 module pulses MP, and 1 tag scan timing pulse STP is generated for every 7 module pulses MP.
One occurs every time a tag ends.

Further, a code is written in the ROM 22 in which each character is represented by a 7-bit binary symbol.

Next, the operation will be explained.

When data is input to the register 21 and a start signal ST is given to the second scan control circuit 37, the motor 33 rotates and the second optical scanner 17 starts scanning in the bar array direction. 35 rotates to generate an output pulse at the timing photoelectric converter 36.

The motor 29 also begins to rotate when the power is turned on.

The output V of the photoelectric converter 19 for laser output detection is given to the first and second scan control circuits 32 and 37, and both motors 29 and 33 have rotational speeds corresponding to the signal V. When the output is large, it rotates at high speed, and when it is small, it rotates at low speed.

Due to the generation of the output pulse of the timing photoelectric converter 36, the timing generation circuit 25 outputs the module pulse ■P and the character pulse CP, and the module pulse M
P is applied to the scanning circuit 23 and the one-turn clutch 31, and the character pulse CP is applied to the register 21.

When character pulse CP is applied to register 21,
Address information for one character from register 21 is stored in ROM 2
2 to designate an address, and 7 bits of barcode information for that character are read out from the ROM 22 at the same time.

This barcode information is applied bit by bit to the optical shutter driver 24 by the scanning circuit 23 in synchronization with the module pulse MP.

A module pulse MP is also applied to the one-turn clutch 31, and when the optical shutter 14 is opened, the one-turn clutch 3
1 operates, the first optical scanner 16 is driven by the motor 29, and (1) a laser beam is projected or not projected for a certain length in the paper transport direction according to the barcode information on the 11 surfaces of the paper sheet during scanning, and this is transmitted to each module. An electrostatic latent image for one character is formed on the paper 11 by repeating each pulse.

When one character is completed and the next character is entered, a character pulse CP is generated from the timing generation circuit 25, the next barcode information is read from the ROM 22, and the 11th side of the paper is optically scanned in the same manner as described above. be exposed.

When the formation of a latent image by optical scanning for one tag is completed, a one-tag scan timing pulse STP is generated from the timing generation circuit 25, which is applied to the paper feed control circuit 28, and the paper feed motor 26 operates to move the paper 11 one by one. Only the number of tags will be transferred.

The next tag position on the paper 11 is detected by detecting the hole 11b in the paper 11.

Thereafter, the same operation as described above is repeated again, and an electrostatic latent image of the desired barcode is formed on the tag, and the developed device 12 visualizes the electrostatic latent image.

Printing is performed in this way, but as mentioned above, the laser tube that serves as the light source for the laser beam deteriorates significantly over time.
At 1N, the exposure gradually becomes insufficient.

However, in the present invention, a detector 19 is provided to detect the output intensity of the laser device 13, and its output voltage V, which is proportional to the intensity of the laser beam, is applied to the control circuits 32 and 37 to control the scanning speed of the optical scanner 16 and 17. is increased or decreased in proportion to the output voltage V, so that the exposure amount of the paper 11 and the light intensity at 0 hours are always kept constant, ensuring proper exposure.

In the above embodiment, the two optical scanners 16 and 17 scan the 11 surfaces of the paper two-dimensionally to form an electrostatic latent image of the barcode. It is also possible to print a bar code by standard scanning, and FIG. 5 shows an outline of its configuration and a control block circuit.

The configuration of the optical system is almost the same as that in FIG. 3 except that the second optical scanner is not required, and the output laser beam of the laser device 13 is transmitted through the mirror 18, the optical shutter 14, and the condensing lens 15. The optical scanner 16
The reflected light is projected towards the 11th side of the paper by the operation of
Scan dimensionally.

On the other hand, the spectroscopy from the -humirror 18 is transmitted to the photoelectric converter 19.
receives the light and converts it into an electrical signal V, and this signal V controls the optical scanning frequency fa.

A control circuit 50 receives the scan frequency fa and sends a drive signal to the driver 30 of the optical scanner 16 and the driver 24 of the optical shutter 14.

When applied to a drum-shaped electrostatic latent image forming body, the optical scanning mechanism shown in FIG.
While arranging second optical scanners 16, 17, etc.,
The rotation of the drum may be controlled in the same manner as the paper feed motor 26 in FIG.

In this case, since the paper may be plain paper, it is suitable for tags and the like that are required to be inexpensive.

Note that the present invention is not limited to the above-described barcode printing device, but can produce the same effects as described above if it is a printer using a light beam.

As explained in detail above, according to the present invention, the required information is accurately and
In addition to being able to print quickly, the output intensity of the laser device is detected by a photoelectric converter and the scanning speed of the optical scanner is controlled according to the detected value, so the exposure amount can always be kept constant regardless of fluctuations in laser output. , it is possible to obtain a clear image and change to high-speed printing when the output of the laser device is low, and to low-speed printing when it is low, so it is recommended to perform high-speed printing by making full use of the capabilities of the device. become capable.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing an example of how a barcode is used, Figure 2 is a schematic configuration diagram to explain the operating principle of photoelectrostatic recording, and Figure 3 is an explanatory diagram showing an example of how a barcode is used.
1 and 4 are a block diagram 1 and a block circuit diagram showing one embodiment of a barcode printing device using a light beam according to the present invention, and FIG. 5 is a configuration diagram showing another embodiment. 2.11... Electrostatic latent image forming body, 6, 12... Developer, 13... Laser device, 14, 16, 17... Optical scanning mechanism, 19... Detector, 32. 37...control circuit.

Claims (1)

[Scope of utility model registration request] a laser device that outputs a light beam with a constant intensity; a modulator that modulates the light beam according to input data; and an optical scanning mechanism that scans and records the surface of a recording medium with an intermittent light beam according to input data; The recording medium is characterized by comprising a detector that detects the intensity of the light beam, and a control circuit that controls the scanning speed of the light beam based on the output of the detector to keep the amount of exposure on the surface of the recording medium constant. A light beam printing device.