JPS62282209A - Encoder - Google Patents

Abstract

PURPOSE:To make speed and position detections available on machines, instruments, etc. moving with a construction without a rotating mechanism, by placing linear heater and temperature sensor in the direct vicinity of a surface and detecting temperature of a heated surface by a temperature sensor. CONSTITUTION:Temperature sensors 4-6 are arranged at the respective distances, l, l+DELTAl, l+2DELTAl from a linear heater in the direction perpendicular to its longitudinal direction. They are consolidated into one body through a partition 3 and screening is made in such a way that heat of the heater 2 does not affect directly use sensor. Next, the heater and sensors 4-6 are made to approach a scanning surface 7 or permitted to contact tightly with the surface and they are made to move in the direction of an arrow A for scanning. And, when an electric current is applied to the heater 2 pulsively with a constant period, a portion of this sheet of paper 7 opposing to the heater 2 is heated and upon reaching of the sensors 4-6 to the heated portion, pulses are issued out corresponding to the temperature. When these pulses are signal- processed by a proper circuit, a series of pulses is obtained. A distance of this series represents scanning speeds and relative positions and by measuring their errors relative to the reference, contribution to various alarms and controls can be available.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention Industrial Application Field This invention relates to an encoder that can detect speed and position without using a nine-turn machine, and relates to an image scanner that inputs one image. , relates to an element applicable to a mouse, which is a manual operation input means of a personal computer.

BACKGROUND OF THE INVENTION Encoders are used to detect speed and position in various devices, and conventional encoders use a rotating system. An example of this will be explained using an image scanner shown in FIG. In the figure, 5 is a hand-held image scanner, and 51 is a light source having an elongated direction, such as an LED array, which illuminates the top of the paper surface 59. The illuminated image 591 on the paper surface is imaged on the one-dimensional image sensor 53 via the lens 52. The image sensor 53 is designed to output a two-dimensional image signal as is well known by the scanner unit 5 rolling and scanning by rollers 541 and 542. An encoder disk 56 is attached to the shaft 55 of the rollers 541 and 542, and slits 57 are provided on the surface thereof at predetermined intervals. The box-shaped member 58 installed to sandwich this disk is a photo coupler. That is, one of the branches 581 has a light emitting source, and the light is received through the slit 57 by a light receiving section embedded in the other branch 582. When the scanner unit 5 moves and scans the paper surface 59, the rollers 541, 5
42 rotates, and the encoder disk 56 also rotates accordingly. Then, the light emitted from the photocoupler 58 is sequentially opened and closed by the slit 57, and its electrical output becomes a pulse train. This pulse train represents the rotation speed of the rollers 541 and 542, that is, the speed of movement and scanning of the camera unit 5 of the image scanner. Furthermore, when viewed from the predetermined pulse position, the position of any pulse can be seen as representing the relative movement distance of the camera units 5.

The image scanner 5 has a moving scanning speed and a reading scan of the one-dimensional image sensor 53 (in a direction perpendicular to the moving scanning).
A predetermined timing is required between the speed of if,
If the moving scanning speed is abnormally fast or too slow, the reproduced image will be distorted, with parts skipping or being jammed. Therefore, if the image scanner 5 is of the type that moves and scans manually, its speed unevenness is detected using the output pulses of the encoder photocoupler 58.
A warning lamp can be lit to notify you. In addition, for image scanners that perform self-propelled moving scanning, such as stationary types, errors in the moving speed are detected from the output pulses of the encoder, and the rotation of the moving scanning motor is controlled to maintain a constant speed. It is also possible to perform a moving scan. Furthermore, if the error is within an allowable range, when a reproduced image is obtained from the image output using a printer or display, the reproduction means can be controlled based on this encoder output pulse train to obtain good image quality. It is possible.

Other encoders include magnetic type, optical reflection type,
Various resistance value change types have been put into practical use.

Problems to be Solved by the Invention However, since all conventional encoders are equipped with a rotation mechanism, they have the following problems.

In other words, in the case of the above-mentioned image scanner, the encoding roller rolls on the paper surface, or if the roller slips, the encoder disk stops for a while, and the output pulse train does not represent accurate speed or position. . Furthermore, if a one-rotation mechanism is provided, the structure becomes more complicated, which is inconvenient when applied to miniaturized equipment. Particularly in devices that are small and move at low speeds, it becomes difficult to extract the pulse train without a mechanism that expands the amount of movement, and conventional encoders have a high R rating. ? There wasn't.

This invention has the following features to solve these conventional problems:
The present invention provides a linear encoder with a structure that does not use any rotation mechanism.

Means for Solving the Problems The encoder of the present invention includes three linear heaters that generate heat when energized, and a plurality of temperature sensors arranged at different intervals in a direction perpendicular to the longitudinal direction of the linear heaters. It includes sensors and a temperature shielding means provided between these temperature sensors and the linear heater. Then, this encoder is moved and scanned on one surface so that the linear heater and the temperature sensor are placed close to or in close contact with one surface, and the temperature sensor detects the temperature of the surface heated by the linear heater. According to the encoder of the present invention, it has a combination structure of a linear heater and a temperature sensor, heats the surface being moved and scanned, and absorbs reflected heat and radiation from the heated surface. The heat is read by a temperature sensor. Therefore, the structure can be made into one small solid element including a rotation mechanism, and can be called a linear encoder. Furthermore, since fA degrees are read, it is suitable for detecting minute intervals of movement.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a bottom view of an encoder according to an embodiment of the present invention, FIG. 2 is a front view, and FIG. 3 is a time chart for explaining the operation of the embodiment.

In the figure, 1 is a linear encoder element, and 2 is a linear heater. 11 is a block portion that supports the heater 2;
4, 5, and 6 are temperature sensors arranged at distances of lc, Ia+Δ1, Jo+2Δ1 in a direction perpendicular to the longitudinal direction of the linear heater 2. This 1 degree sensor 4+
For example, a thermistor is used as 5+6.

Reference numeral 12 denotes a block portion that supports these temperature sensors 4, 5, and 6, and is adjacently integrated with the other block portion 11 via the partition wall 3. This partition wall 3 has a temperature shielding effect to prevent direct influence on the heat side of the linear heater 2.

7 is the surface that the linear enhancer 1 moves and scans.

In the case of an image scanner, it is a paper surface such as a printed matter. A linear heater 2 and a temperature sensor 4 . ．． 5.8 is close to or in close contact with arrow A
Move and scan in the direction of. Then, the linear heater 2 is energized by pulses h having intervals of a constant period To, for example, as shown in FIG. Then, the linear heater 2 on page 7
The linear portion facing and passing through is heated. When the temperature sensor 4, 5.6 reaches the heated lower surface according to the moving scan.

Pulses corresponding to the temperature are sequentially output as shown in FIG. 3 a, b, and c. Then these output pulses a.

When signals b and c are processed by an appropriate circuit, a pulse having a time period Δ° C. that becomes pulse train d is obtained. The interval between the pulse train d thus obtained indicates the speed and relative position of the moving scan. Here, the scanning speed is determined as V = △1/△, and the error can be measured with respect to the standard, which can contribute to various warnings and controls.

The temperature sensor is a first sensor located within the width of the linear heater 2 in the longitudinal direction and at a distance of io from the heater 2.
Wo! After that, the temperature sensors are placed at the same distance of 6 and Δl at the position Δii apart, and the scanning speed v
(=Δ1/Δ°C) is obtained.

Therefore, in one temperature sensor, the number of heating lines between the linear heater and the sensor is as follows.

The scanning speed cannot be detected because it is not known how many lines can be produced depending on the scanning speed.

Therefore, the l basin level sensor requires two or more sensors separated by ΔIH1.

The detection processing of the output pulses a, b, and c of the temperature sensor may be performed by taking out the average value or the maximum value and performing the detection process using direct current. Further, the linear heater 2 may be one in which the tip m portions 21, 22, and 23 facing the plane of the paper are arranged discontinuously as shown in FIG. 4. In addition, various other modifications may be considered.

Effects of the Invention As described above, according to the present invention, there is no nine-rotation mechanism, and therefore there is no occurrence of errors due to slips when detecting the speed or position of equipment moving along the scanning surface. . Further, due to its structure, it can be made quite compact and lightweight, making it effective when applied to small equipment. Furthermore, since it reads temperature, it is suitable for detecting minute intervals of movement, and there are many possible uses for it.

[Brief explanation of the drawing]

FIG. 1 is a bottom view of an embodiment of the encoder of the present invention;
FIG. 2 is a front view of the same embodiment, and FIG. 3 is a time chart for explaining the operation of the same embodiment. FIG. 4 is a bottom view of another embodiment, and FIG. 5 is a perspective perspective view showing the structure of an image scanner using a conventional encoder. 1...Fog encoder, 2...Wire heater, 3φΦO partition wall as temperature cutoff means, 4-6...1 temperature sensor. Patent applicant: NEC Home Electronics Co., Ltd.
1 Figure 2 Figure 3

Claims (2)

[Claims] (1) A linear heater that generates heat when energized, a plurality of temperature sensors arranged at different intervals in a direction perpendicular to the longitudinal direction of the linear heater, and a combination of these temperature sensors and the linear heater. and a temperature cutoff means provided between the linear heater and the temperature sensor, the linear heater and the temperature sensor are placed close to or in close contact with one surface, and the temperature of the one surface heated by the linear heater is detected by the temperature sensor. An encoder characterized in that the encoder moves and scans the one surface as shown in FIG. (2) The encoder according to claim (1), wherein the linear heater is energized in pulses at predetermined time intervals.