JP2001113804A - Method and apparatus for inspecting product of printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for inspecting a product for guaranteeing performance of an ink jet printer body using a replaceable ink jet head cartridge without actually printing. SOLUTION: An ink jet printer body 1 has a carriage 6, a sheet feeding roller disposed oppositely to the carriage 6 to convey a printing sheet or the like. A speed unevenness sensor 9 is mounted at the cartridge 6 instead of an ink head cartridge. Further, in the body 1, a speed measuring unit 11 for processing an output from the sensor 9, an FFT analyzer 12, and a deciding unit 10 for deciding whether good or not of the speed unevenness of the carriage and the roller from the result processed by them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a product inspection method in a printer production process.

[0002]

2. Description of the Related Art In recent years, an ink jet printer which discharges ink to print on a recording medium (for example, paper) has been widely used. Among these ink jet printers, there is a type in which the recording head, which is an ink ejection unit, is not only black with a cartridge type but can be replaced with a color head,
Such printers have been widely used because they are compact and inexpensive as products that can perform black and color printing. Conventionally, in a product inspection in the production process of an ink jet printer having this replaceable ink head cartridge, the ink head cartridge is actually mounted on a scanning carriage and printed, and the printing condition is assured by an operator by observing the printing state. Was.

FIG. 6 is an inspection configuration diagram when a conventional product inspection method is performed. As shown in FIG. 1, the ink jet printer main body 1 has a color or black ink head cartridge 61 mounted thereon, a carriage 6 for reciprocating scanning on a straight line, an operation unit 7 for starting the printer main body 1, and an ink head cartridge. And a paper supply unit (not shown) for installing a print paper 62 to be supplied to a print area 61.

FIG. 7 is an operation flow when a conventional product inspection method is performed. First, the inspector sets the actually printable color or black ink head cartridge 61 on the carriage 6 of the ink jet printer main body 1 (step S51), and prints the printing paper 6 on the paper supply unit.
2 is set (step S52). When the operator operates the operation unit 7 (step S53), the inspection pattern is output (printed) on the printing paper 62 (step S5).
4). The inspector takes out the printed printing paper 62 from the printer main body 1 (step S55), inspects the output state of the head, and determines pass / fail (step S56).
Finally, the inspector removes the ink head cartridge 61 from the carriage 6 (Step S57).

When the output state of the head is inspected, a vertical line is printed in a direction intersecting (for example, at right angles) with the carriage scanning, that is, in a sub-scanning direction in which the ejection nozzles are arranged. For example, printing is performed on the effective width area of the printing paper in a state where the dots are arranged at 3-dot intervals (so-called line chart), or the dots are thinned out at a fixed ratio in the main scanning direction (carriage scanning direction) and the sub-scanning direction to enable the effective width. The evaluation was made by printing on the area (so-called halftone printing).

[0006] Regarding the paper feed unevenness, a horizontal line is printed in the main scanning direction, and the horizontal line is formed into a line chart in the vertical width effective printing area of the printing paper or at least one rotation of all gears constituting the paper feeding mechanism. The evaluation was made by printing the paper for the required feed width or by printing halftone as in the inspection of carriage scanning unevenness.

[0007]

However, the above conventional example has the following problems.

[0008] In this inspection, the printing time is enormous, and if the inspector does not take in other work just in time for the printing time during printing, wasteful time is generated.
The management was hard. Also, the evaluation itself includes factors of variation of the ink head cartridge itself by actually printing, that is, variations in ejection or non-ejection of each nozzle, and factors of variation on the paper feed side. Was difficult.
Since the sensory test is performed by visual inspection, a clear standard value cannot be set, and an accurate determination may not be made. Usually, in the case of a visual inspection, the criterion is a sample, which is called a limit sample, which is just before the specification of a good or defective product. Pass / fail is determined by comparing the sample with the sample. Even if the same test target printing paper is evaluated, the results vary among the inspectors. In particular, in a delicate judgment close to the limit sample, if several people make a judgment on a trial, the result is always different.

An object of the present invention is to provide a product inspection method and a product inspection apparatus which guarantee the performance of an ink jet printer using a replaceable ink jet head cartridge without actually printing.

[0010]

According to a first aspect of the present invention, there is provided a transporting roller for transporting a recording sheet, the scanning roller intersecting with the transporting direction of the recording sheet and being exchangeable. A method for inspecting a product of a printer, comprising: a carriage holding a recording head, wherein a speed unevenness sensor having a shape and weight equivalent to the recording head is mounted on the carriage instead of the recording head; and The method includes a step of performing scanning in the same operation state as during printing, and a step of determining whether or not the carriage speed unevenness detected using the speed unevenness sensor during the carriage scanning is good or bad.

According to a second method of the present invention, a product inspection of a printer having a transport roller for transporting recording paper and a carriage for scanning in a direction intersecting the transport direction of the recording paper and holding a replaceable recording head is provided. A method, wherein, in place of the recording head, a speed unevenness sensor equivalent in shape and weight to the recording head is mounted on the carriage.
The method further comprises the steps of: operating the transport roller in the same operating state as during printing; and determining whether the transport roller speed unevenness detected by the speed unevenness sensor during the transport roller operation is good or bad.

According to a third aspect of the invention, there is provided a product inspection of a printer having a transport roller for transporting a recording sheet and a carriage for scanning in a direction intersecting the transport direction of the recording sheet and holding a replaceable recording head. A method, wherein, in place of the recording head, a speed unevenness sensor having a shape and weight equivalent to the recording head is provided on the carriage.
Scanning the carriage in the same operating state as during printing, stopping the carriage at a predetermined position on the transport roller, operating the transport roller in the same operating state as during printing, and scanning the carriage. And determining whether the carriage speed unevenness and the conveyance roller speed unevenness detected using the speed unevenness sensor during the operation of the conveyance roller are good or bad.

According to a first aspect of the present invention, there is provided a printer having a transport roller for transporting recording paper and a carriage for scanning in a direction intersecting the transport direction of the recording paper and holding a replaceable recording head. A product inspection device, wherein a speed non-uniformity sensor having a shape and weight equivalent to the recording head, which is installed in place of the recording head, and the sensor when the carriage is operated according to a predetermined program. Processing an output signal to detect unevenness in the speed of the carriage, and a determining unit that determines whether the unevenness in the speed of the carriage output from the uneven speed detecting unit is good or not. I do.

According to a second aspect of the present invention, there is provided a product inspection of a printer having a transport roller for transporting a recording sheet and a carriage for scanning in a direction intersecting the transport direction of the recording sheet and holding a replaceable recording head. An apparatus, wherein a speed unevenness sensor having a shape and weight equivalent to the recording head, which is installed in place of the recording head, and an output from the sensor when the transport roller is operated according to a predetermined program. A signal processing unit that detects unevenness in the speed of the transport roller; and a determination unit that determines whether the unevenness in the speed of the transport roller output from the unevenness detecting unit is good or not. And

According to a third aspect of the present invention, there is provided a product inspection of a printer having a transport roller for transporting a recording sheet and a carriage for scanning in a direction intersecting the transport direction of the recording sheet and holding a replaceable recording head. An apparatus, which is installed in place of the recording head, when a speed unevenness sensor equivalent in shape and weight to the recording head and the carriage and the transport roller are sequentially operated according to a predetermined program. Processing the output signal from the sensor, speed unevenness detecting means for detecting the speed unevenness of the carriage and the conveying roller, and the quality of the speed unevenness of the carriage and the conveying roller output from the speed unevenness detecting means. Determining means for determining.

In the above-described apparatus, it is conceivable that the uneven speed sensor is a laser Doppler sensor.

(Operation) In the above-described invention, a speed unevenness sensor is mounted on the carriage of the printer instead of the recording head, and the scanning unevenness and the paper feeding unevenness of the carriage are evaluated based on the output of the sensor. Since there is no need to set the recording paper in the
It is possible to determine in a short time whether or not the scanning unevenness of the carriage to be inspected or the paper feeding unevenness is satisfied, and it is possible to greatly reduce the conventional large inspection time associated with actual printing. Moreover, since the determination is made by the device from the sensor output, the determination is more reliable than the conventional vague visual sensory test. As described above, the inspection can be performed reliably and in a short time. In addition, since neither recording paper nor ink is used, the inspection cost can be significantly reduced.

[0018]

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

FIG. 1 is an inspection configuration diagram for implementing a product inspection method of an ink jet printer as one embodiment of the present invention. As shown in this figure, a carriage 6 that reciprocally scans in a direction intersecting with the transport direction of a printing paper or the like is provided on the inkjet printer main body 1 to be inspected.
An operation unit 7 for operating the printer main body 1 in a desired operation; a memory 3 storing a program such as an inspection sequence of the printer main body 1; a controller 4 for controlling the carriage 6; A CPU 2 that reads a predetermined program from the memory 3 and causes the controller 4 to scan the carriage 6 in accordance with the program;
The display unit 5 includes a paper feed roller (not shown) that is arranged to face the carriage 6 and conveys printing paper and the like. An uneven speed sensor 9 is mounted on the carriage 6 instead of the ink head cartridge. Since the speed unevenness sensor 9 is attached to the carriage 6 instead of the ink head cartridge, it has the same shape as the outer shape of the ink head cartridge. Further, the detection section itself of the sensor 9 is disposed at a position corresponding to the ink discharge nozzle section of the ink head cartridge.

Further, the printer main body 1 as described above has a speed measuring device 11 and an FFT analyzer 12 for processing the output from the speed unevenness sensor 9 and, based on the result of processing by these, a speed unevenness of the carriage and the paper feed roller. A judgment device 10 for judging pass / fail is provided.

FIG. 2 is an operation flow when the product inspection method according to the present invention is performed. First, the inspector attaches the uneven speed sensor 9 to the carriage 6 of the printer main body 1 (step S1), and switches the operation state of the printer main body 1 to the carriage inspection mode by the operation unit 7 for starting the inspection (step S2). In response to this operation, the CPU 2 in the printer body 1 reads out the program of the carriage speed inspection sequence from the memory 3 and sends a signal based on the contents to the controller 4 to scan the carriage 6 in the same manner as when printing. During the scanning, the uneven speed sensor 9 attached to the carriage 6 detects the speed of the carriage 6 (step S3). Then, the sensor output is processed by the speed measuring device 11 and the FFT analyzer 12 to detect carriage speed unevenness (step S4), and the result is sent to the determination device 10.

After detecting uneven carriage speed, the CPU
2 reads out the program of the paper feed speed inspection sequence from the memory 3 and sends a signal based on the content to the controller 4 to move the carriage 6 to an arbitrary position in the effective width printing area (step S5). Further, the CPU 2 causes the controller 4 to operate a paper feed roller (not shown) in the same manner as during printing, and during the operation, the uneven speed sensor 9 on the carriage 6 detects the speed of the paper feed roller (step S6). Then, similarly to the carriage speed unevenness detection, the speed sensor 11 and the FFT analyzer 12 process the sensor output to detect the paper feed speed unevenness (Step S).
7) The result is sent to the determination device 10.

Thereafter, the results of detection of the uneven carriage speed and the uneven paper feed speed are evaluated in the judgment device 10 (steps S8 and S9), and a pass / fail judgment is made (step S10). Here, for example, in the evaluation for quality determination, the speed unevenness signal obtained in steps S4 and S7 is converted into a position variation signal by an integration operation (step S8), and a determination standard ± number to an assumed reference print position is obtained. It is determined whether the distance is within several tens of μm (step S9).

In order to end the inspection, finally, the uneven speed sensor 9 is removed from the carriage 6 (step S1).
1).

FIG. 3 is an explanatory diagram of the operation when detecting uneven carriage speed. The carriage 6 is scanned in the main scanning direction (carriage scanning direction) at the same speed as during printing in a state where the speed unevenness sensor 9 is attached to the carriage 6. This scanning is the same as in normal printing, but the range measured by the sensor is only the effective printing area, and the range outside both sides is not measured because there are acceleration fluctuation and deceleration fluctuation of the carriage operation. However, due to the operation of the carriage,
Since that range is also scanned and has nothing to do with the measurement time,
The acceleration region and the deceleration region may also be measured by a sensor, and the speed fluctuation of the carriage in that region may be taken as data.

FIG. 4 is an explanatory diagram of the operation when the unevenness of the paper feed speed is detected. The uneven speed sensor 9 is the carriage 6
The paper feed roller 41 is driven in the sub-scanning direction (paper feed direction) at the same speed as when printing. At this time, the carriage 6 has stopped in the effective print area on the paper feed roller 41. In the effective printing area, the portion that directly stops in the effective printing area is the portion that directly contacts the paper, so that the paper feed roller 41 has a uniform shape (circular shape), and the sensor reading due to the change in the shape. No mistakes will occur. However, depending on the product, if the roller shape is not uniform (for example, there is a projection) even within the effective printing area, control is performed so that the carriage 6 does not stop at that location. Conversely, the carriage 6 may be stopped at a position outside the effective printing area as long as the shape is readable by the sensor in the same manner as in the area.

FIG. 5 is a diagram for explaining speed fluctuations of the carriage 6 and the paper feed roller 41. Uneven speed sensor 9
For example, a laser Doppler sensor emits a laser from the carriage 6 toward the platen or the paper feed roller 41, and detects a speed variation from a waveform change of the reflected wave. FIG. 5 shows the relationship between carriage speed and time,
The carriage speed is detected by a laser Doppler sensor, converted into an analog signal by a speed measuring device 11, and the signal is
Output to FT analyzer 12. Then, the FFT analyzer 12 calculates the speed fluctuation rate. The speed fluctuation rate is defined by the following equation. Speed fluctuation rate = (ΔV / V) × 100
(%) Here, V is the average speed, and ΔV is the speed variation.
The uneven speed sensor 9 mounted on the carriage 6 is configured to have the same weight as the ink head cartridge so that measurement can be performed under the same conditions as actual printing. The same sensor is optimally used for the uneven carriage speed and the uneven paper feed speed. However, if it is desirable to measure with a different sensor due to, for example, a difference in the reading speed, a different sensor may be used.

[0028]

As described above, according to the present invention, a speed unevenness sensor is mounted on the carriage of the printer instead of the printhead, and unevenness of scanning of the carriage and unevenness of paper feed can be obtained without actually printing with the printhead. Since the evaluation is performed, it is possible to determine in a short time whether or not the carriage scanning unevenness or the paper feeding unevenness to be inspected is satisfactory, and it is possible to greatly reduce the conventional large inspection time associated with actual printing. In addition, since the determination is made by the device from the sensor output, the determination is more reliable than the conventional vague sensory test. As described above, the inspection can be performed reliably and in a short time. In addition, since neither recording paper nor ink is used, the inspection cost can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is an inspection configuration diagram for implementing a product inspection method of an ink jet printer as one embodiment of the present invention.

FIG. 2 is an operation flow when the product inspection method according to the present invention is performed.

FIG. 3 is an operation explanatory diagram when carriage speed unevenness is detected in the product inspection method according to the present invention.

FIG. 4 is an explanatory diagram of an operation when unevenness in paper feed speed is detected in the product inspection method according to the present invention.

FIG. 5 shows a carriage 6 and a paper feed roller 4 shown in FIGS. 3 and 4;
FIG. 4 is a diagram for explaining a speed fluctuation of No. 1;

FIG. 6 is an inspection configuration diagram when a conventional product inspection method is performed.

FIG. 7 is an operation flow when a conventional product inspection method is performed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printer main body 2 CPU 3 Memory 4 Controller 5 Display part 6 Carriage 7 Operation part 9 Speed unevenness sensor 10 Judgment device 11 Speed measuring instrument 12 FFT analyzer 41 Paper feed roller

Claims (7)

[Claims] 1. A product inspection method for a printer, comprising: a transport roller that transports a recording sheet; and a carriage that scans in a direction intersecting the transport direction of the recording sheet and that holds a replaceable recording head. Mounting a speed unevenness sensor having a shape and weight equivalent to the printhead on the carriage instead of the printhead; scanning the carriage in the same operating state as during printing; and Determining whether the carriage speed unevenness detected by using the unevenness sensor is good or bad. 2. A product inspection method for a printer, comprising: a conveying roller for conveying a recording sheet; and a carriage for scanning in a direction intersecting the conveying direction of the recording sheet and holding a replaceable recording head. In place of the recording head, a stage in which a speed unevenness sensor equivalent in shape and weight to the recording head is mounted on the carriage, a stage in which the transport roller is operated in the same operation state as during printing, and a stage in which the transport roller operates. Determining whether the transport roller speed irregularity detected using the speed irregularity sensor is good or bad. 3. A product inspection method for a printer, comprising: a transport roller that transports a recording sheet; and a carriage that scans in a direction intersecting with the transport direction of the recording sheet and that holds a replaceable recording head. Installing a speed unevenness sensor having the same shape and weight as the printhead on the carriage in place of the printhead; scanning the carriage in the same operating state as during printing; and Stopping at a predetermined position above, operating the transport roller in the same operation state as during printing, and uneven carriage speed and transport roller detected by using the speed unevenness sensor during the carriage scanning and the transport roller operation. Determining the quality of the speed unevenness. 4. A product inspection apparatus for a printer, comprising: a transport roller that transports a recording sheet; and a carriage that scans in a direction intersecting the transport direction of the recording sheet and holds a replaceable recording head. A speed unevenness sensor installed in place of the printhead, the shape and weight of which are equivalent to the printhead, and processing an output signal from the sensor when the carriage is operated according to a predetermined program, A printer product inspection apparatus, comprising: speed unevenness detecting means for detecting speed unevenness of the carriage; and determining means for judging whether the speed unevenness of the carriage outputted from the speed unevenness detecting means is satisfactory. 5. A product inspection apparatus for a printer, comprising: a transport roller that transports a recording sheet; and a carriage that scans in a direction intersecting the transport direction of the recording sheet and that holds a replaceable recording head. A speed unevenness sensor having a shape and weight equivalent to the printhead installed in place of the printhead, and processing an output signal from the sensor when the transport roller is operated according to a predetermined program. A printer product comprising: uneven speed detecting means for detecting uneven speed of the transport roller; and determining means for determining whether or not the uneven speed of the transport roller is output from the uneven speed detecting means. Inspection equipment. 6. A product inspection apparatus for a printer, comprising: a transport roller that transports a recording sheet; and a carriage that scans in a direction intersecting the transport direction of the recording sheet and that holds a replaceable recording head. A speed non-uniformity sensor having a shape and weight equivalent to the print head installed in place of the print head, and an output from the sensor when the carriage and the transport roller are sequentially operated according to a predetermined program A signal processing unit that detects unevenness in speed of the carriage and the transport roller; and a determination unit that determines whether the speed unevenness of the carriage and the transport roller output from the uneven speed detector is good or bad. A product inspection device for a printer, comprising: 7. The product inspection device for a printer according to claim 4, wherein the speed unevenness sensor is a laser Doppler sensor.