JPH0626892A - Recorder - Google Patents

Abstract

PURPOSE:To reduce cost of a means for detecting pen carriage position and obtaining feedback signal by constituting of minimum part number and simple structure without loosing necessary detection values. CONSTITUTION:A pen carriage 10 moving to the direction perpendicular to the recording paper 1 running direction is provided. On the opposit side of the pen carriage pen, a CCD linear sensor 20 is contacted. Facing to this CCD linear sensor and in parallel to the recording paper, a scale 22 having light shielding effect is provided. On the other side of the scale, a light source 23 for casting light on the CCD linear sensor is arranged. The position of the pen carriage is detected with the scale and the CCD linear sensor in the constitution and it is fedback.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention records various recording data such as various measured values including temperature, humidity, etc., their measuring conditions, conditions, etc. on a belt-shaped recording paper as a chart by a pen cartridge or the like. More specifically, the recorder will be described in more detail. A feedback system for a servo mechanism that feeds back the position of a recording element such as a recorder or a plotter to follow an input, particularly a contactless feedback type recorder that employs an optical absolute feedback system. Regarding

[0002]

2. Description of the Related Art There are analog servos and digital servos as position servos for controlling a load (such as a pen) at a target position according to the input of a recorder. Correspondingly, analog servos and digital servos are used as feedback elements. There are two types of shapes.

Most of the general recorders use a sliding resistance potentiometer linked to the position of the pen as an analog feedback element. Initially, a wire-wound potentiometer was used, but a conductive plastic (CP) type potentiometer is often used because of its life. However, due to the mechanical sliding portion, poor contact, generation of noise, deterioration of linearity, etc. are inevitable.

Therefore, various measures have been taken in order to make the feedback element non-contact and improve the reliability. That is, as such a non-contact type analog feedback element, there are, for example, a rotary ring type differential transformer, a rotary type capacitance type converter, a magnetostrictive delay line type displacement converter and the like. All of them are non-contact type, but they have many components and tend to be inferior to the conductive plastic potentiometer in terms of cost.

A contactless digital encoder utilizing light, magnetism, or electrostatic capacity is also known, and there are an incremental type and an absolute type, which are several μm.
It is effective when applied to a robot or NC machine tool that requires high accuracy such as sensitivity.

However, the recording width of the pen in the recorder is 300
Since the required sensitivity is about 100 μm, the expensive digital encoder as described above is not suitable for practical use.

Therefore, by making the feedback element non-contact, and obtaining an absolute signal corresponding to the pen position and combining it with a microprocessor,
A low cost intelligent recorder has been proposed in the past, for example, in Japanese Patent Laid-Open No. 64-50914.

That is, in this conventional apparatus, a CCD linear sensor installed parallel to a pen carriage installed so as to travel in a direction perpendicular to the running direction of the band-shaped recording paper is provided, and is formed by extending from the pen carriage. The CCD linear sensor is illuminated by the optical fiber attached to the extension arm, and by electrically reading it, the current position of the pen is converted into an absolute digital signal, and the servo loop is operated so that this matches the input signal. Is what you are doing.

According to this structure, the CCD
Since the linear sensor appropriately obtains a digital absolute value proportional to the pen position, a multifunctional intelligent recorder can be easily constructed.

[0010]

However, in the above-mentioned conventional apparatus, the CCD linear sensor having the detection width which is equal to or larger than the recording width of the recording paper is provided along the moving range of the pen carriage. There is a problem in that this CCD linear sensor becomes large in size and costly because it is necessary.

An optical fiber is required as means for irradiating the CCD linear sensor with light to detect the position of the pen carriage, and only the light from the optical fiber is received by the CCD linear sensor. In addition, it is necessary to form a closed space by providing a light-shielding member such as a cover so that external light, dust, etc. do not enter, which increases the number of component parts, complicates the structure, and raises the cost. There was also the problem of doing.

In particular, in the above-mentioned conventional apparatus, in order to read by the CCD linear sensor with the SELFOC microlens attached to the optical fiber, the above-mentioned closed space and other constituent parts are included in order to prevent mixing of light from the outside. Since the number of points is large and the structure is complicated, it is desired to solve the problems.

The present invention has been made in view of the above circumstances, and the moving position of the pen carriage can be detected easily and reliably, and the number of constituent parts is small.
Another object is to obtain a recorder having a simple structure and capable of reducing the cost.

[0014]

In order to meet such a demand, the recorder according to the present invention comprises a pen carriage that moves in a direction orthogonal to the traveling direction of the recording paper. A light source for connecting a CCD linear sensor on the opposite side, providing a scale having a light-shielding property so as to face the CCD linear sensor and parallel to the recording paper, and irradiate the CCD linear sensor with light across the scale. Is arranged, the position of the pen carriage is detected by the scale and the CCD linear sensor, and this is used as a feedback signal.

[0015]

According to the present invention, the CCD linear sensor provided on the side of the pen carriage which moves in the direction orthogonal to the running direction of the recording paper, the scale provided facing the CCD linear sensor and parallel to the recording paper, and the scale By using a light source that emits light from the back side of the pen, the light from the light source is received by the CCD linear sensor through the scale, and the position of the pen carriage is detected by the change in the light-shielding property of the scale. It is used as a feedback signal for the input signal of the carriage.

[0016]

1 to 4 show an embodiment of a recorder according to the present invention. In this embodiment, a case of a continuous writing 2-pen recorder is illustrated. In these figures, first, the main structure of the recorder will be briefly described with reference to FIG. 1 and FIG. 2. The recording paper indicated by reference numeral 1 is a sprocket 2.
By the rotation of the sprocket shaft 3 in the arrow direction, the sprocket shaft 3 is fed at a constant speed in the arrow direction in FIG. Then, the first pen P1 and the second pen P2 are arranged at a predetermined interval in the width direction of the recording paper 1 so as to record required data. The pens P1 and P2 have the same configuration, operation, and operation, and only one of them will be described.

That is, the pen carriage 10 is guided by the guide rod 11 and slides in a direction orthogonal to the traveling direction of the recording paper 1. The guide rod 11
Both ends of are fixed to side plates (not shown).

A pin 12 penetrates the pen carriage 10, and the pen carriage 10 holds a pen holder 13 rotatably by the pin 12. A cassette pen P1 is inserted into the pen holder 13 to record an analog record K. When the pen P1 is removed, the pen holder 13 rotates counterclockwise around the pin 12 as a rotation center, and a stopper 14 that is an extension of the pen holder 13 is provided.
Hits the pen carriage 10 and is prevented from tilting any further.

Further, reference numeral 15 in the drawing denotes an arm having one end connected to the rear end side of the pen carriage 10 with a screw 16,
Is a ball bearing provided at the other end of the arm 15, and 18 is a guide rail for guiding the ball bearing 17 in a direction orthogonal to the traveling direction of the recording paper 1.

Reference numeral 19 in the drawing denotes a tension thread fixed on the pen carriage 10 by a screw 19a. When the tension thread 19 is pulled by a servo motor (not shown), the pen carriage 10 is guided by the guide rod 11 and Axial direction,
That is, the recording paper 1 slides in a direction orthogonal to the traveling direction.

Reference numeral 20 denotes a CCD linear sensor mounted on the back side of a printed circuit board 21 which is erected in a direction orthogonal to the other end of the arm 15, and 22 denotes a fixed portion side facing the CCD linear sensor 20. The CCD linear sensor 20 and the scale 2 provided on the scale
2 is the part that characterizes the present invention.

That is, according to the present invention, the portion of the pen carriage 10 which is a movable member that moves in the direction orthogonal to the traveling direction of the recording paper 1 on the side opposite to the pen P1 is shown in FIG.
As is clear from FIG. 4, the CCD linear sensor 20 is provided so as to be connected to the CCD linear sensor 20. The CCD linear sensor 20 faces the light receiving surface of the CCD linear sensor 20 in parallel and has the light shielding property at an appropriate position so as to be parallel to the recording paper 1. The scale 22 is provided, and the CCD linear sensor 2 is sandwiched by the scale 22.
The light source 23 for irradiating light to the
The position of 0 corresponds to the scale 22 and the CCD linear sensor 2
It is characterized in that it is detected by 0 and used as a feedback signal.

Here, in this embodiment, the scale 22 and the CCD linear sensor 20 are arranged so that the longitudinal direction thereof is the same as the arrangement direction of the elements. The scale 22
Both ends of are fixed to side plates (not shown), and are installed with a distance such that they do not contact the CCD linear sensor 20.

According to such a structure, the CCD linear sensor 20 provided on the side of the pen carriage 10 which moves in the direction orthogonal to the traveling direction of the recording paper 1, and the CCD linear sensor 20 which faces the recording surface in parallel and records. Scale 22 parallel to paper 1
And a light source 2 that emits light from the back side of the scale 22.
By using 3 and 3, the light from the light source 23 is received by the CCD linear sensor 20 via the scale 22, and the position of the pen carriage 10 is detected by the change in the light shielding property of the scale 22, and this is detected by the pen carriage 10. It is used as a feedback signal for the input signal.

Here, the scale 22 in this embodiment is used.
3 and 4, bars 22a are printed on a transparent plastic plate at equal intervals of a pitch P. The printed bars 22a have a width from the left side to the right side of the CCD linear sensor. It is gradually expanded within the range that can be detected by. Of course, such a bar 22a is provided with a pitch such that at least one bar 22a is within the scanning range of the CCD linear sensor 20. Also, this pitch and the bar 22a
It is preferable that the width of the pen is registered in the memory of the CPU in advance, and the output of the CCD linear sensor 20 is analyzed to calculate the position of the pen.

In this embodiment, the case where the transparent plastic plate is used has been described, but the present invention is not limited to this, and it is needless to say that the same function can be obtained by forming a slit in the opaque plastic or metal plate instead of printing. Yes. The point is that the scale 22 is made of a plate material in which bar code-shaped stripes are printed or slits, and the position can be detected by reading the bar code of the scale 22 with the CCD linear sensor 20.

Further, in the recorder as described above,
The analog input to this recorder can be digitized by an A / D converter after amplification. Therefore, the CPU
Is scaled or linearized to become a digital input signal. This and CCD linear sensor 20
, And the servo loop operates so that this becomes 0, and the pen carriage 10 is moved to stop at the equilibrium point. Although a digital servo loop configuration method and the like are well known and there are various methods, detailed description thereof will be omitted.

FIGS. 5 and 6 show another embodiment of the recorder according to the present invention. In this embodiment, the scale 22 described above is formed on a transparent plastic plate along the moving direction of the pen carriage. The light-shielding portion 22b having a substantially triangular shape is printed with light-shielding paint. The CCD linear sensor 20 has a scale 2 like this.
On the other hand, the scale 22 is provided on the pen carriage 10 side, which is a movable part, with the photodetection part 20a capable of detecting the light-shielding part 22b and the transmissive part 22c in the vertical width direction. There is.

Here, the triangular light-shielding portion 22b printed on the scale 22 described above gradually extends from the left side (0%) to the right side (100%) within a range that can be detected by the light detecting portion 20a of the CCD linear sensor 20. It has been expanded to Of course, the left and right of such a scale 22 may be reversed. In addition, a in FIG. 5 is a maximum width dimension of the light shielding portion 22b, which is within a width of the effective screen of the CCD linear sensor 20.

Further, in this embodiment, it is preferable that the longitudinal direction of the scale 22 and the arrangement direction of the elements of the CCD linear sensor 20 are perpendicular to each other.

In such a structure, when the pen carriage 10 moves from the left side to the right side, the light entering the CCD linear sensor 20 is gradually blocked, so that a sensor output signal having a constant relationship with the moving amount is generated. . This CC
The relationship between the output of the D linear sensor 20 and the position of the pen carriage 10 is registered in advance in the memory of the CPU.
The output of the CCD linear sensor 20 is analyzed by the pen P
It is advisable to calculate the position such as 1.

Although a transparent plastic plate is also used in this embodiment, it will be easily understood that the same function can be obtained by forming a slit in an opaque plastic plate or a metal plate instead of printing. . In short, a pattern may be formed so that the amount of the light shielding portion 22b increases or decreases along the moving direction of the pen carriage 10.

It will be easily understood that the present invention is not limited to the structure of the embodiment described above, and various modifications and changes can be made to the shape and structure of each part of the recorder. For example, although the two-pen type recorder has been described in the above-mentioned embodiment, it is needless to say that the present invention is not limited to this, and a dot recording mechanism can be obtained by attaching a dot mechanism to the portion of the pen carriage.

[0034]

As described above, according to the recorder of the present invention, the CCD linear sensor is connected to the opposite side of the pen carriage of the pen carriage which moves in the direction orthogonal to the traveling direction of the recording sheet, and the CCD linear sensor is connected to the CCD linear sensor. A scale having a light-shielding property is provided so as to face the linear sensor and be parallel to the recording paper, and a light source for irradiating the CCD linear sensor with light sandwiching the scale is provided, and the position of the pen carriage is Since the scale and the CCD linear sensor are used for detection and used as a feedback signal, the movable CCD linear sensor and the fixed scale are used in spite of the simple structure with the minimum required number of parts. By using the light source on the back side,
It is possible to receive the light from a light source through a scale with a CCD linear sensor, detect the position of the pen carriage by the change in the light shielding property of the scale, and use this as a feedback signal to the input signal of the pen carriage. Since the structure is simpler than that of the conventional one, and in particular, only a small CCD linear sensor needs to be used, there are various excellent effects that the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing an embodiment of a two-pen type recorder to which the present invention is applied.

FIG. 2 is a schematic side view of FIG.

FIG. 3 is a schematic diagram showing an example of a scale that characterizes the present invention.

FIG. 4 is a schematic plan view showing the relationship between the scale of FIG. 3 and a CCD linear sensor.

FIG. 5 is a schematic view showing a modified example of the scale that characterizes the present invention.

6 is a schematic rear view showing the relationship between the scale of FIG. 5 and a CCD linear sensor.

[Explanation of symbols]

 1 Recording Paper 2 Sprocket Shaft 10 Pen Carriage 11 Guide Rod 12 Pin 13 Pen Holder 15 Arm 17 Ball Bearing 18 Guide Rail 20 CCD Linear Sensor 21 Printed Circuit Board 22 Scale 22a Bar 22b Light-shielding Part 22c Light Transmitting Part 23 Light Source P1 1st Pin P2 No. 2 pin

Claims (1)

[Claims] 1. A pen carriage which moves in a direction orthogonal to a running direction of a recording sheet is provided, and a CCD linear sensor is connected to the side of the pen carriage opposite to the pen.
A scale having a light-shielding property is provided so as to face the CD linear sensor and be parallel to the recording paper, and a light source for irradiating the CCD linear sensor with light sandwiching the scale is provided, and the position of the pen carriage is adjusted. A recorder which is configured to detect by the scale and the CCD linear sensor and feed back this.