JPH01101413A - Recorder - Google Patents

Abstract

PURPOSE:To perform recording with high accuracy at all times by detecting the position of a pen at plural positions and performing open-loop control over the pen position according to the corrected quantity of the detected movement quantity of the pen under open-loop control. CONSTITUTION:A CPU 5 sets a channel for an analog input signal a1 and puts an A/D converter 3 in operation. Then the CPU 5 finds how many steps of a stepping motor 10 the recording position of the signal a1 passes from the reference position at the left end of recording paper 12. Here, this recording position is stored as yp(-n) in a RAM 36. Then the CPU 5 finds the number of steps of the motor 10 from position data on the pen 15 which is stored in last recording operation, the number of rotations of the stepping motors 10 driven in the last and current times, and the span correction coefficient of the pen 15 and sets this value for a stepping motor driver 6.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a recorder that records various analog signals in waveforms on recording paper using a pen, and in particular, a recorder that is equipped with an open-loop control function for pen position. Concerning improvements to recorders.・ (Prior art) Recorders have been used that record various analog signals in waveforms on recording paper using a pen, but one of them is a recorder that has a function for short-term open-loop control of the pen position. Many recorders are being used. In other words, this recorder uses a step motor as the pen drive mechanism, and moves from the pen recording position (current recording position) corresponding to the input signal to the current pen position (previous recording position) to the current recording position. The recording operation is performed by determining the number of steps (drive amount) and step rotation direction of the step motor for moving the pen. However, in this type of recorder, once the pen position is shifted due to some reason (disturbance), it cannot return to the normal recording position from the shifted position, so subsequent recordings are completely unreliable. It becomes.

Therefore, in recent years, a technique for solving such problems has been proposed by the present applicant in "Japanese Patent Application No. 1983-71175". In other words, this recorder periodically detects the actual position of the pen while the pen is moving and recording in response to an analog input signal, and detects the pen position corresponding to the detected pen position and the analog input signal. The pen position is corrected by determining the number of steps and step rotation direction of the step motor that moves the pen from the recorded position. However, although this type of recorder can adequately handle the disturbances mentioned above, it does not detect the pen position during open-loop control, so if the mechanical system such as the diameter of the motor pulley or reeling If there is an error in , the recording error will increase as the pen moves, causing a problem in recording accuracy.

Incidentally, problems in recording accuracy due to the existence of such errors in the mechanical system also apply to the above-mentioned recorder.

(Problems to be Solved by the Invention) As described above, in various conventional recorders, if there is an error in the mechanical system such as the diameter of the motor boob or the diameter of the reel, the recording error will increase and the recording accuracy will be affected. There was a problem.

An object of the present invention is to provide a recorder that can always perform highly accurate recording even if there are errors in mechanical systems such as the diameter of the motor pulley and the diameter of the reel.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a motor that moves the pen from a recording position of the pen corresponding to an input signal and a current pen position. In a recorder equipped with an open-loop control function that performs a recording operation by determining the drive amount of A calibration operation means for calculating a correction amount of the pen movement amount by open-loop control based on each detected pen position.

(Function) Therefore, in the present invention, by providing the above means, the pen position at a plurality of locations by open loop control is detected by the pen position detection means, and based on the respective pen positions, the pen position is detected by open loop control. A correction amount of the pen movement amount is calculated by the calibration operation means. Then, the drive amount of the motor that moves the pen is determined from the calculated correction amount of the pen movement amount, the recording position of the pen corresponding to the input signal, and the current pen position. The recording operation is performed with the error eliminated.

(Example) First, the concept of the present invention will be described.

Now, if the two pens are at the 0% position and we are performing pen position detection and error correction, which is feedback control, there is no error here and all pens are at the 4th position.
As shown in Figure (a), it is exactly at the 0% position. Next, if all pens are moved to the 100% position by performing only open-loop control on the pens, if nothing is taken into consideration as in the conventional example, for example, as shown in FIG. 4(b), There may be errors in the actual pen position. As mentioned above, the cause of this error is that the amount of pen movement from 0% to 100%, that is, the span is 1. For example, even if it is determined to be 1000 steps of a step motor, which is a motor for driving a pen, in reality, it may vary from the set value due to mechanical errors such as the diameter of the motor bore and the reeling diameter.

- Therefore, the present invention includes a calibration operation means. That is, as shown in FIG. 4(a), all pens are 0.
After aligning the % positions, all the pens are moved to the 100% position by open loop control, and the pen positions are detected again at the position shown in FIG. 4(b). And the fourth
By subtracting from this the detected position in figure Cb'), the actual span S1. S2 (SN is the span of the Nth pen, the unit is %) is found. and,
In the subsequent open-loop control, if you want Atsushi N Ben to move by X%, it will actually move by X%.
Error correction is performed by moving not only % but also (x·100/SN)%. With this method, from the position where all pens are aligned at 0%, 1
In the case of 00% positional rotation, it becomes possible to accurately align all the pens as shown in FIG. 4(C).

The variation in span is mainly due to the diameter of the motor pulley and reeling diameter, and is proportional to the distance the pen moves, so if the movement from 0% to 100% is accurate, it goes without saying that any Movement from one point to another becomes more accurate. In other words, accurate recording can be performed in the entire recording range only by performing negative point calibration.

Furthermore, the above-mentioned error factors are stable over time;
Long-term correction is possible by performing - degree calibration operation.

An embodiment of the present invention based on the above concept will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an example of the structure of a recorder according to the present invention. In FIG. 1, each analog signal aln82 is
are input to analog/digital converters (hereinafter referred to as A/D converters) 3.4 via amplifiers 1 and 2, respectively,
It is now converted to a digital signal. On the other hand, a step motor driver 6.7 and a chart driver 8 are connected to the central processing unit (hereinafter referred to as CPU) 5 via a path line 9, and these step motor drivers are operated according to instructions output from the CPU 5. 6.
7 and chart driver 8 are operated. Here, the step motor driver 6 receives data on the step rotation direction, pulse rate, and number of steps of the step motor 10 and drives the step motor 10 in step rotation.
Similarly to the step motor driver 6, the step motor driver 6 receives data on the step rotation direction, pulse rate, and number of steps of a step motor (not shown) and drives the step motor in step rotation. Furthermore, the chart driver 8 receives the chart and speed data and controls the number of revolutions of the chart motor 11 so that the recording paper 12 reaches the relevant speed.
It moves the .

On the other hand, on the opposite side of the pen carriages 13 and 14 from where the pens 15 and 16 are provided, there are provided photointerrupters 17 and 18 that are composed of a light emitting element and a light receiving element. The photo interrupter 17 generates a pen position detection signal indicating that the actual position of the pen 15 has been detected when the protrusion 13a formed on the pen carriage 13 enters between the light emitting element and the light receiving element and blocks the light. In addition, when the protrusion 14a formed on the Ben carriage 14 enters between the emitting element and the light receiving element and blocks the light, the photo ink printer 18 outputs the actual light of 4 in 16. A pen position detection signal indicating that the position has been detected is output.

Both of these photo ink printers 17 and 18 are
The sensor carriage motor 2.0 is driven and controlled by the sensor carriage driver 19, and the pens 15, 16 are configured to move in parallel with the direction of movement thereof. This movement is achieved by attaching a sensor carriage 25 provided with photo interrupters 17 and 18 to the reeling yarn 24 stretched between the pulleys 21, 22 and 23, and rotating the sensor carriage motor 20 through the gears 26 and 27. This is done by being transmitted to the pulley 23 via the link. Each pen position detection signal output from each photo ink printer 17, 18 is input to an interrupt controller 28.

On the other hand, a gear 2 provided on the rotating shaft of the step motor 10
9 rotates, the gear 30 that meshes with the gear 29 rotates, and the reeling line 33 tensioned on the pulleys 31 and 32 operates, so that the Benn carriage 13 attached to the reeling line 33 moves on the shaft 34. It looks like this.

In addition to the function of recording operation processing A shown in FIG. 2, the CPU 5 moves the sensor carriage 25, which is a pen position detection means, as shown in FIG. and 100% position rotation (earliest position).

It has a function of a calibration operation process B that calculates the pen movement amount correction amount, that is, the span correction coefficient, for all the pens 15 and 16 by open loop control based on the pen position detection signal. In addition, 35 is a ROM (read only memory) that stores each program of the above processing A and B.
36 is a RAM (random access e-memory) for storing various data during processing and as a result of processing.

Next, the operation of the recorder configured as described above will be explained with reference to the flowcharts shown in FIGS. 2 and 3.

First, the calibration operation will be described with reference to the calibration operation processing flow diagram shown in FIG.

The calibration operation process is executed prior to the recording operation process described later. The CPU 5 outputs a drive command to the sensor carriage driver 19 in step S11. As a result, the sensor carriage and Tsuji motor 20 are rotationally driven to move the sensor carriage 25 to the home position.
For example, it is moved to the left end position of the recording paper 12. Next, in step S12, the CPU 5 outputs a drive command to the sensor carriage driver 19, thereby causing the sensor carriage motor 20 to rotate and move the sensor carriage 25 in parallel to the moving direction of the pen 15, 16. The pen is moved (scanned) once from the home position to detect all current pen positions. That is, by moving the sensor carriage 25, the photointerrupter 1
Each protrusion 13a, 14a of the pen carriage 13.14 passes between each light emitting element and light receiving element of 7.18, and this passage corresponds to the position of each pen 15.16, and this time A pen position detection signal is output from each photointerrupter 17 and 18. On the other hand, if the CPU 5 allows interrupts only during the outward movement of the sensor carriage 25, the pen position detection signals output from each photo ink printer 17, 18 are sent to the CPU 5 through the interrupt controller 28. Here, each current pen 15
．． 16 positions are stored in the RAM 36.

After detecting the current position of each pen 15, 16 in this way, the process moves to step S13, where the CPU 5 calculates the number of steps of the step motor and sets this value to the step motor driver 6. . This results in
Step motor 1 compatible with step motor driver 6
0. A step motor (not shown) corresponding to the step motor driver 7 is driven to rotate step by step, and each gear 29, 30 . The gear (not shown) corresponding to the step motor driver 7 rotates, and the reeling yarn 33 and the reeling yarn (not shown) act to move the Benn carriage 13.14 of each pen 15.16, thereby reducing each pen 15.16 to 0%. Move it to the appropriate position.

As a result, the positions at which the pens 15 and 16 stop vary due to various error factors, as described above. Therefore, in step S14, the CPU 5 moves (scans) the sensor carriage 25 once in the same manner as described above, and determines the actual position of each pen 15° 16 at the 0% position x □ (15), x O([1) is detected and stored in the RAM 36. Next, step S15
In the same manner as described above, the CPU 5 controls each pen 15.1.
6 to the position equivalent to 100%. Then, in step S16, the CPU 5 moves (scans) the sensor carriage 25 once in the same manner as described above, and determines the actual position of each pen 15.16 at the 100% position x 1i0(15) , x 10G (18) is detected and stored in the RAM 36.

Finally, in step S17, the CPU 5
From the pen positions x 100(15) and x 100(16) stored in step S16 and detected in step S16,
Pen position X o (15)+ detected in step S14
By subtracting x□(1B), the spans S(15) and S(1B) corresponding to 100% of each actual pen 15.16 by open loop control are obtained. That is,
Even if the Nth pen is moved 100% by open loop control, the actual movement is S N (= x 100 (
N)
It is 00%.

In other words, a · 100/ (xloo(N)
By moving (N) 1%, it actually moves by a%, and this 100/ (xloo(N)
It can be obtained as a pen span correction coefficient kN.

As described above, each pen 15° and 16th span correction coefficient k15. k18 is determined and stored in the RAM 36, and the calibration operation process is completed.

Next, the recording operation will be described with reference to the recording operation processing flow diagram shown in FIG.

The recording operation process is executed at relatively short intervals, for example, every 100 is. The CPU 5 sets the channel rP-IJ for the analog input signal a1 in step s1, and operates the A/D converter 3 in the next step s2. As a result, the analog input signal is converted into a digital signal, which is stored in the RAM 36 in step s4 based on the determination in step S3. When the A/D conversion of the analog input signal a1 is completed and the storage operation in the RAM 36 is completed, the process proceeds to the next step S5, and the CPU 5 determines that the recording position of the analog input signal a1 is, for example, a reference point at the left end of the recording paper 12. The number of steps of the step motor 10 is calculated from the position. Here, this recording position is stored in the RAM 36 as yp(-n).

Next, in step S6, the CPU 5 calculates the position data x p(n
-1), step motor 10 driven between previous and current
The theoretical value x p (n) of the current position of the pen 15 is calculated from the step rotation direction and the number of steps m (n-1), and the span correction coefficient k15 of the pen 15 stored during the configuration operation described above. X p (n) - X p (n-1) + m
Calculate using (n-1)/k 15. Then, proceeding to the next step S7, the above y p(n), x
From p(n) and the span correction coefficient k15 of the pen 15,
The number of steps of the step motor 10 and the step rotation direction required to move this theoretical pen position value x p (n) to the position y p (n) are expressed as k15- (y p (n) - x p (n) ) value for step motor driver 6' shell. As a result, the step motor 10 rotates in steps to drive each gear 2, 9, and 3.
0 rotates, and the reeling thread 33 acts to move the pen carriage 13, thus recording on the recording paper 12. The recording operation process as described above is executed for each channel P, and recording is performed for each analog input signal al+82. In this case, a calibration operation is performed in advance and the span correction coefficient k15 is set for each pen 15.16. klB is determined, and this span correction coefficient k15. Since errors during open-loop control are corrected by k18, highly accurate recording operations can be performed with the mechanical system errors mentioned above eliminated.

As described above, the recorder of this embodiment performs a calibration operation to determine the span correction coefficient k15.16 for each pen 15.16. 1B is calculated for , and errors during open loop control are corrected in advance by adding 15°k16 to this span correction coefficient, so even if there are mechanical errors such as motor pulley diameter or yarn reeling diameter, This makes it possible to always perform highly accurate recording even if the movement spans of the pens vary due to errors in the drive mechanism of each pen 15, 16.

It should be noted that the present invention is not limited to the embodiments described above, but can be similarly implemented as follows without changing the gist thereof.

(a) In the above embodiment, the calibration operation does not necessarily need to be performed at the 0% and 100% positions; if the pen has a wider movable range, it may be performed at, for example, -10% and +110% positions. good.

(b) In the above embodiment, the means for detecting the position of the pen is not limited to a photo ink probe, but may also be a Hall element or a means using ultrasonic waves, and furthermore, the means for detecting the position of the pen may be, for example, a means for emitting light on the pen carriage side. It is also possible to provide a structure in which a light-receiving element is provided on the sensor carriage side.

(c) In the above embodiment, the pen driving mechanism is not limited to the step motor, but any mechanism that can be controlled in an open loop may be used.

(d) In the above embodiment, the present invention is applied to a recorder equipped with two pens, but the present invention is not limited to this.
The present invention can be similarly applied to recorders equipped with more than one pen.

[Effects of the Invention] As explained above, according to the present invention, the pen position is detected at a plurality of locations, and the open loop control of the pen position is performed based on the correction amount of the pen movement amount by open loop control calculated from the pen position detection. This makes it possible to provide an extremely reliable recorder that can always perform highly accurate recording even if there are errors in mechanical systems such as the diameter of the motor pulley or the diameter of the reel.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of a recorder according to the present invention;
FIGS. 2 and 3 are flowcharts for explaining the operation of the same embodiment, and FIGS. 4(a) to 4(c) are conceptual diagrams for explaining the present invention in detail. 1.2...Amplifier, 3.4...A/D converter, 5.
...CPU, 6.7...Step motor driver, 8
...Chart driver, 9...Pass line, 10.
...Step motor, 11...Chart motor, 12
... Recording paper, 13.14 ... Pen carriage, 13
a. 14a...Protrusion, 15.16...Pen, 17.1
8... Photo interrupter, 19... Sensor carriage driver, 20... Sensor carriage motor, 2
1゜22.23...Pulley, 24...Reeling thread, 25.
...Sensor carriage, 26.27...Gear, 28.
...Interrupt controller, 29.30...Gear, 31
．． 32...Pulley, 33...Reeling, 34...Shaft, 35...ROM, 36...RAM0 Applicant's agent Patent attorney Takehiko Suzue 82Figure 3

Claims (1)

[Claims] In a recorder equipped with an open-loop control function that performs a recording operation by determining the drive amount of a motor that moves the pen from the recording position of the pen corresponding to an input signal and the current pen position, the recorder is in a non-contact state with the pen. a pen position detection means for detecting the position of the pen at a point; and a calibration for calculating a correction amount of the pen movement amount by the open loop control based on each pen position detected at a plurality of locations by the pen position detection means. A recorder comprising: operating means.