JP2000302109A - Encoder abnormality detecting device and information writing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an encoder abnormality detecting device for detecting the abnormality of the encoder by a simple constitution. SOLUTION: In an encoder abnormality detecting device for detecting the abnormal operation of an encoder 10 outputting respectively first pulse signals and second pulse signals of different output periods respectively, the first pulse signals and the second pulse signals are counted respectively, and the count numbers are compared with to judge the abnormality of the encoder 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an encoder abnormality detecting device capable of detecting an operation abnormality of an encoder outputting a first pulse signal and a second pulse signal having different output periods, and an encoder using the encoder. The present invention relates to an information writing device for positioning a printing object.

[0002]

2. Description of the Related Art Generally, various information such as the date of manufacture and the number of lots are displayed on a mass-produced beverage, food, or other product at a manufacturing stage.

The display of such various kinds of information is performed, for example, by writing on a label attached to a product in order to display the contents, or by writing directly on a product container. .

For example, for bottle products such as beverages,
When the label is attached to the bottle container filled with the contents in the manufacturing stage, necessary information is written to a predetermined position of the label by laser light or ink jet immediately before the attachment.

A device for writing information on a label includes a transport mechanism for transporting the label and a printing mechanism for printing. The transport mechanism transports the label to a printing position, and the label reaches the printing position. Printing by the printing mechanism at the timing, that is, irradiation of laser light,
Alternatively, ejection of ink or the like is performed.

The timing at which the label reaches the printing position by the transport mechanism is detected by, for example, an encoder that outputs a signal in conjunction with the movement of the transport mechanism. And
By controlling the transport mechanism and the printing mechanism so that printing is performed in accordance with the timing detected using the encoder, necessary information can be written at a predetermined position on the label.

[0007]

However, in the above-described apparatus, if an error occurs in the output signal of the encoder for some reason, printing is performed at an incorrect timing, so that the printing position is shifted. .

As a technique for coping with such an accident, Japanese Patent Application Laid-Open No. H10-1121 discloses an information writing device in which a conveyed label is detected by a reflection type position detection sensor. . In this device, the count number of the encoder at the time when the signal from the position detection sensor is output is monitored, and if the count number is out of the appropriate range, it is determined that an abnormality has occurred in the encoder.

However, in the apparatus disclosed in Japanese Patent Application Laid-Open No. 10-1121, it is necessary to provide a position detection sensor separately from the encoder, and the configuration of the entire apparatus becomes complicated. Further, for example, if the position detected by the position detection sensor changes, the appropriate range of the count number also changes, so that there is a problem that it takes time and effort to install and maintain the apparatus.

[0010] The present invention provides an encoder abnormality detecting device capable of detecting an encoder abnormality with a simple configuration,
It is another object of the present invention to provide an information writing device that does not require installation and maintenance work.

[0011]

According to a first aspect of the present invention, there is provided an encoder for outputting a first pulse signal and a second pulse signal having different output periods, respectively.
A first counter (16) for counting a first pulse signal output from the encoder (10), and a second pulse signal output from the encoder (10). And a first counter (1)
A determination unit (16) for determining the abnormality of the encoder (10) by comparing the number of counters of (6) with the number of counts of the second counter (16).

According to the present invention, since the abnormality of the encoder (10) is detected based on the pulse output from the encoder (10), the encoder (10) can be installed without changing the equipment in which the encoder (10) is installed. Abnormality can be detected.

According to a second aspect of the present invention, an abnormal operation of an encoder (10) for outputting a first pulse signal (A-phase pulse) and a second pulse signal (Z-phase pulse) having different output periods is provided. In an encoder abnormality detection device for detecting, a counter (16) whose start / stop is controlled by using a second pulse signal (Z-phase pulse) as a trigger, and a first pulse signal counted by the counter (16) (A-phase pulse) is compared with a preset reference count to determine an abnormality of the encoder (10).

According to the present invention, the abnormality of the encoder (10) is detected based on the pulse output from the encoder (10). Therefore, the encoder (10) can be installed without changing the equipment in which the encoder (10) is installed. Abnormality can be detected.

According to a second aspect of the present invention, the period of the second pulse signal (Z-phase pulse) is longer than the period of the first pulse signal (A-phase pulse). May be.

According to a fourth aspect of the present invention, there is provided a positional relationship changing means for changing a relative positional relationship between a printing position at which printing is to be performed and a printing medium (R), and a printing position. And an encoder that outputs a first pulse signal (A-phase pulse) and a second pulse signal (Z-phase pulse) having different output periods as signals according to the relative positional relationship between substrates (R). (10) and a position detecting means (10) for detecting that the printing object (R) has been positioned at the printing position based on the first pulse signal (A phase) and the second pulse signal (Z phase pulse). , 12, 14)
A printing means (6) for performing printing on the printing substrate (R) when the positioning is detected by the positioning detection means (10, 12, 14); a first pulse signal (A-phase pulse); Abnormality detecting means (16) for detecting abnormality of the encoder (10) based on the pulse signal (Z-phase pulse)
And the following.

In the present invention, since the abnormality of the encoder (10) is detected based on the pulse output from the encoder (10), a sensor or the like for detecting the position of the substrate (R) is provided separately from the encoder (10). There is no need to provide
The configuration of the entire apparatus can be simplified. In addition, since installation of a sensor or the like is not required, no trouble is required for installation work and maintenance work.

According to a fourth aspect of the present invention, in the information writing apparatus according to the fifth aspect, the abnormality detecting means counts a first pulse signal (A-phase pulse) output from the encoder. A counter (16); a second counter (16) for counting a second pulse signal (Z-phase pulse) output from the encoder (10);
Determining means (16) for determining whether the encoder (10) is abnormal by comparing the counter number of the counter (16) with the count number of the second counter (16).

According to a fourth aspect of the present invention, in the information writing apparatus according to the sixth aspect, the abnormality detecting means uses a second pulse signal (Z-phase pulse) as a trigger to start / stop counting.
A counter (16) whose stop is controlled, and a counter (1
(6) comparing the count number of the first pulse signal (A-phase pulse) counted with the preset reference count number to determine an abnormality of the encoder (10); May be provided.

According to a sixth aspect of the present invention, the period of the second pulse signal (Z-phase pulse) is made longer than the period of the first pulse signal (A-phase pulse). You may.

In the information writing apparatus according to any one of claims 4 to 7, as in claim 8, as the positional relationship changing means, a label transport means for transporting the print medium (R) toward the printing position. (1, 2) may be provided.

[0022] In the information writing apparatus according to any one of claims 4 to 8, the printed matter may be a label (R).

In the information writing apparatus according to any one of the fourth to ninth aspects, when an abnormality of the encoder is detected by the abnormality detecting means, the printing by the printing means may be stopped.

In order to facilitate understanding of the present invention, reference numerals in the accompanying drawings are appended in parentheses, but the present invention is not limited to the illustrated embodiment.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which an encoder abnormality detecting device and an information writing device according to the present invention are applied to a label printing machine (labeler) will be described below with reference to FIGS.

As shown in FIG. 1, the present label printing machine includes a rotary cylinder 1 mounted rotatably about a rotary shaft 1A, and a plurality of pallets 2 provided along the outer periphery of the rotary cylinder 1. , A glue roller 3 for applying glue to the pallet 2, a label magazine 4 for supplying the labels R one by one to the pallet 2, a label R for receiving the label R from the pallet 2, and attaching the label R to the bottle W conveyed by the belt conveyor V. And a laser oscillator 6 for irradiating the label R on the pallet 2 with a laser beam.

As shown in FIG. 1, an optical rotary encoder 10 is mounted on a rotary shaft 1A of the rotary cylinder 1, and a signal corresponding to the rotation angle of the rotary cylinder 1 is output from the rotary encoder 10. The shaft 11 of the rotary encoder 10 that rotates according to the rotation of the rotation shaft 1A (FIG. 2)
Is mounted with a disk on which a predetermined optical pattern is formed. By reading this optical pattern using a light emitting element and a light receiving element, a signal corresponding to the rotation angle of the rotary cylinder 1 is output.

The rotary encoder 10 outputs a Z-phase pulse once and an A-phase pulse and a B-phase pulse 500 times each time the shaft 11 makes one rotation. The cycle of the Z-phase pulse coincides with the cycle in which the pallet 2 faces the laser oscillator 6. That is, each time one Z-phase pulse is output, printing is performed on one label R. The A-phase pulse and the B-phase pulse have a relationship in which the phases are shifted from each other by 90 degrees. Since the configuration of such an optical rotary encoder is known, detailed description is omitted.

FIG. 2 is a control block diagram showing a control system of the label printing machine. As shown in FIG. 2, an A-phase pulse, a B-phase pulse,
The phase pulse is input to the multiplier 12. The multiplier 12 captures the rising edges of the A-phase pulse and the Z-phase pulse, converts the A-phase pulse and the Z-phase pulse into an A′-phase pulse and a Z′-phase pulse having a pulse voltage of 5 V and a pulse width of 5 μSec, respectively, and outputs them. I do.

FIG. 3 is a diagram showing the waveforms of the A 'phase pulse and the Z' phase pulse output from the multiplier 12. As shown in FIG. 3, from the multiplier 12,
An A′-phase pulse having a period of 200 μSec and a pulse width of 5 μSec and a Z′-phase pulse having a period of 100 mSec and a pulse width of 200 μSec are output. Although FIG. 3 shows a case in which labels are printed and attached to 600 bottles W per minute, the horizontal axis (time axis) in FIG. 3 is actually the driving of the label printing machine. It fluctuates according to the speed.

In the control board 14 shown in FIG.
The A′-phase pulse is counted using the Z′-phase pulse as a trigger, and a shot signal is output when a predetermined count is reached. The laser oscillator 6 emits laser light toward the label R with the shot signal as a trigger.
The predetermined count is set to a value such that when the rotary encoder 10 is operating normally, printing is correctly performed at a predetermined position on the label.

As shown in FIG. 2, the A′-phase pulse and the Z′-phase pulse output from the multiplier 12 are also input to the pulse isolator 15. Similarly to the multiplier 12, the pulse isolator 15 captures the rising edges of the A-phase pulse and the Z-phase pulse, and converts the A-phase pulse and the Z-phase pulse into a pulse voltage of 5 V and a pulse width of 8, respectively.
The signal is converted into an A ″ -phase pulse and a Z ″ -phase pulse of 0 μSec and output to the sequencer 16. FIG. 4 shows the waveforms of the A ″ -phase pulse and the Z ″ -phase pulse output from the pulse isolator 15.

The sequencer 16 shown in FIG. 2 determines whether the rotary encoder 10 is operating normally by comparing the A '' phase pulse and the Z '' phase pulse. Specifically, for example, the A ″ -phase pulse is counted by using the Z ″ -phase pulse as a trigger, and whether the rotary encoder 10 is normal or abnormal is determined based on the counted number.

As shown in FIG. 2, the label printing machine is provided with a labeler control panel 20 for controlling the operation of the printing machine. The label control panel 20 outputs a signal notifying the operation of the label printing machine to the sequencer 16. Further, the sequencer 16 outputs a signal to the labeler control panel 20 to notify the abnormality of the encoder. When the labeler control panel 20 receives the signal indicating the abnormality of the encoder, the operation of the label printing machine, that is, the rotation of the rotary cylinder 1 and the operation of the laser oscillator 6 are immediately stopped.

Further, a warning light 17 is connected to the sequencer 16 to notify that the label printing machine is under inspection or that an abnormality has occurred in the label printing machine.

Next, an example of the abnormality detection processing of the encoder 10 executed in the sequencer 16 will be described with reference to the flowchart of FIG.

In step S1 of FIG. 5, it is determined whether or not the operation of the label printing machine has been started. After the determination is affirmed, the process proceeds to step S2. The determination in step S1 is made based on the presence or absence of the above-mentioned signal indicating the operation of the label printing machine output from the label control panel 20.

In step S2, reset processing of various parameters including resetting of a counter for counting the A ''-phase pulse is performed, and the process proceeds to step S3.

In step S3, the process waits for the input of the Z '' phase pulse, and then proceeds to step S4.
Then, a command to start the counting of the A ''-phase pulse is issued to the counter. This counter can be realized by another process executed in parallel in the sequencer 16. In addition, A ″ is used by using an apparatus other than the sequencer 16.
Phase pulses may be counted. Next, in step S5, after waiting for the input of the Z ″ phase pulse, the process proceeds to step S6, and the counter is instructed to end the counting of the A ″ phase pulse.

By the processing in steps S3 to S6, a Z '' phase pulse is output (step S3), and then the next Z '' phase pulse is output (step S5).
The number of pulses of the A ″ phase pulse up to this point is counted.

Next, in step S7, it is determined whether or not the count number of the counter is 480 or less. If the determination is affirmative, the process proceeds to step S10, and if the determination is negative, the process proceeds to step S8. In step S8, it is determined whether or not the count number of the counter is 520 or more. If the determination is affirmative, the process proceeds to step S10, and if the determination is negative, the process proceeds to step S9. In step S10, the above-mentioned signal for notifying the encoder of abnormality is transmitted to the labeler control panel 20, and the alarm lamp 17 is turned on to notify the operator of the abnormality of the encoder, and thereafter, the process is terminated. On the other hand, in step S9, the counter is reset and the process returns to step S3, and thereafter, the A ″ phase pulse counting process is repeated.

In steps S7 to S10,
When the count number is 480 or less or the count number is 520 or more, it is determined that the encoder is abnormal. If the rotary encoder 10 is operating perfectly, the A-phase pulse should be output 500 times during one cycle of the Z-phase pulse. As shown in FIG. Should be 500. However, actually, the optical pattern may not be able to be partially read due to the contamination of the disk or the like. In the present embodiment, the case where the count number is 480 or less or the count number is 520 or more is determined to be abnormal, so that the operation of the label printing machine is not stopped frequently while keeping the print position deviation within an allowable range. ing. In the present embodiment, since the shift width of the print position when the count number of the A ″ phase pulse fluctuates by 20 pulses corresponds to 10 mm, the allowable value of the print shift width is set to a maximum of ± 10 mm. Will be.

Note that the range of the count number for distinguishing the normal / abnormal of the encoder 10 can be set arbitrarily according to the allowable range of the printing position deviation in each case. In the present embodiment, the count number can be manually switched.

In this embodiment, the abnormality of the encoder 10 is detected based only on the pulse output from the encoder 10. Therefore, the sensor for detecting the position of the label R for detecting the abnormality of the encoder 10 is used. No need to install Therefore, the configuration of the entire apparatus can be simplified, and the installation and maintenance of the apparatus can be simplified.

Further, in this embodiment, by adding the additional portion Ad of FIG. 2 to a normal label printing machine,
Although it is possible to detect an abnormality that has occurred in the encoder 10,
The pulse isolator 15 and the sequencer 16 included in the additional portion Ad can both be general-purpose products and are inexpensive. Moreover, in this embodiment, the bottle W
Even during label printing and sticking operations at a high speed of 1200 lines, it is possible to accurately detect the abnormality of the encoder 10.

In this embodiment, the A ″ phase pulse is triggered by the Z ″ phase pulse, ie, the Z phase is triggered,
That is, the A-phase pulse is counted, and the abnormality of the encoder is detected based on the count number.
An abnormality of the encoder may be detected by counting the phase pulse and the Z-phase pulse for a predetermined time and comparing the count numbers of both. In this embodiment, the abnormality of the encoder is detected based on the count number of the A-phase pulse during the counting of one Z-phase pulse. The first to count
And a second counter that counts the A-phase pulse while counting one Z-phase pulse.

In this embodiment, the printing position is fixed and the label is conveyed to the printing position. However, it is possible to print the fixed label or the moving label while moving the printing position. You may comprise.

[0048]

According to the first and second aspects of the present invention, the abnormality of the encoder is detected on the basis of the pulse output from the encoder. Abnormality can be detected.

According to the fourth aspect of the present invention, the abnormality of the encoder is detected based on the pulse output from the encoder. Therefore, it is not necessary to provide a sensor for detecting the position of the printing material separately from the encoder. The configuration of the entire apparatus can be simplified. In addition, since installation of a sensor or the like is not required, no trouble is required for installation work and maintenance work.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a label printing machine to which an information writing device according to the present invention is applied.

FIG. 2 is a control block diagram showing a control system of the label printing machine.

FIG. 3 is a timing chart showing output signals of a multiplier.

FIG. 4 is a timing chart showing output signals of a pulse isolator.

FIG. 5 is a flowchart showing processing in the sequencer.

[Explanation of symbols]

 Reference Signs List 1 rotating cylinder 2 pallet 6 laser oscillator 10 rotary encoder 12 multiplier 14 control board 16 sequencer R label

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[Procedure amendment]

[Submission date] April 27, 2000 (200.4.2
7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

[0011]

According to a first aspect of the present invention, there is provided an encoder for outputting a first pulse signal and a second pulse signal having different output periods, respectively.
A first counter (16) for counting a first pulse signal output from the encoder (10), and a second pulse signal output from the encoder (10). And a first counter (1)
A determination means (16) for determining the abnormality of the encoder (10) by comparing the number of counters of (6) with the count number of the second counter (16). ) Is provided with a range in the range of the count number determined to be normal.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction contents]

According to a second aspect of the present invention, an abnormal operation of an encoder (10) for outputting a first pulse signal (A-phase pulse) and a second pulse signal (Z-phase pulse) having different output periods is provided. In an encoder abnormality detection device for detecting, a counter (16) whose start / stop is controlled by using a second pulse signal (Z-phase pulse) as a trigger, and a first pulse signal counted by the counter (16) (A-phase pulse) is compared with a preset reference count to determine an abnormality of the encoder (10). ) Is provided with a range in the range of the count number determined to be normal.

Claims (9)

[Claims] 1. An encoder abnormality detection device for detecting an operation abnormality of an encoder that outputs a first pulse signal and a second pulse signal each having a different output cycle, wherein the first pulse signal output from the encoder A first counter that counts the number of pulses, a second counter that counts the second pulse signal output from the encoder, and a counter number of the first counter and a count number of the second counter. A determination unit for determining abnormality of the encoder. 2. An encoder abnormality detection device for detecting an operation abnormality of an encoder that outputs a first pulse signal and a second pulse signal having different output periods from each other. A counter whose start / stop is controlled, and a judging means for judging abnormality of the encoder by comparing the count number of the first pulse signal counted by the counter with a preset reference count number, An encoder abnormality detection device comprising: 3. The cycle of the second pulse signal is equal to the first pulse signal.
3. The encoder abnormality detecting device according to claim 2, wherein the period of the pulse signal is longer than the period of the pulse signal. 4. A positional relationship changing means for changing a relative positional relationship between a printing position at which printing is to be performed and a printing material, and a relative position relationship between the printing position and the printing material. An encoder that outputs a first pulse signal and a second pulse signal whose output periods are different from each other as a signal; and the printing medium is at the printing position based on the first pulse signal and the second pulse signal. Positioning detection means for detecting that the positioning has been performed; printing means for performing printing on the printing medium when positioning is detected by the positioning detection means; and a first pulse signal and a second pulse signal. An information detecting device for detecting an abnormality of the encoder based on the information. 5. The method according to claim 1, wherein the abnormality detecting unit counts the first pulse signal output from the encoder.
A counter for counting the second pulse signal output from the encoder; and a counter for counting the number of counters of the first counter and the number of counts for the second counter. The information writing apparatus according to claim 4, further comprising: a determination unit configured to determine an abnormality of the information. 6. The abnormality detection means includes: a counter for controlling start / stop of counting by using the second pulse signal as a trigger; and a count number of the first pulse signal counted by the counter in advance. The information writing apparatus according to claim 4, further comprising: a determination unit configured to determine an abnormality of the encoder by comparing the reference count number with a set reference count number. 7. The cycle of the second pulse signal is the first pulse signal.
7. The information writing device according to claim 6, wherein the period of the pulse signal is longer than the period of the pulse signal. 8. The information writing apparatus according to claim 4, further comprising a label transport unit that transports the print target toward the printing position as the positional relationship changing unit. . 9. The information writing apparatus according to claim 4, wherein the printing medium is a label.