JP2011022019A - Object detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide inexpensively a miniaturizable detection device excellent in detection accuracy and resolution. <P>SOLUTION: This device 1 for detecting existence, a size or a moving amount of an object includes: a lever part 71 comprising an optically transparent resin, and having a contact capable of abutting on the object, wherein the contact is displaced following abutment of the object; a scale part 72 formed in a body from the same material as the lever part 71, and displaceable corresponding to displacement of the lever part 71, wherein many shielding domains and translucent domains are formed alternately in the displacement direction; a light source 6 for irradiating the scale part 72 with light; and a photodetector 4 for receiving light transmitted through the scale part 72. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an apparatus for detecting the presence / absence, size, or movement amount of an object.

  For machines such as printing presses, scanners, automatic ticket gates, vending machines, ATMs, etc., it is required to detect the presence, size, or amount of movement of handling objects such as paper, tickets, and banknotes during the supply or discharge process. Is done.

  This type of detection device includes an upper and lower roller disposed facing a paper supply path, an LED and a PSD, a lever instead of the LED and PSD, and a reflector attached to the rear end of the lever. And a photosensor that emits light toward the reflector and receives the reflected light is known (Patent Document 1 [Prior Art] column). As shown in FIG. 11, the former is normally urged by the spring 103 in the direction in which the upper roller 101 approaches the lower roller 102, and is moved up by the thickness of the paper against the restoring force of the spring 103 when the paper passes. The roller 101 moves away from the lower roller 102, and the displacement amount of the upper roller 101 is optically detected by the LED and PSD. In the latter case, as shown in FIG. 12, the lever 104 is pivotally fixed to a fulcrum, the tip of the lever 104 is connected to the shaft of the upper roller 101, and the lever 104 is always moved by the spring 103. Is urged in a direction to approach the lower roller 102, and the photo sensor 105 detects the amount of displacement of the rear end of the lever 104 that swings as the paper passes.

  Further, by improving this, as shown in FIG. 13, the rear end of the lever 104 is branched into a plurality of branches 106, or the rear end of the lever is fan-shaped to provide a radial slit so that the light of the photo interrupter passes. A device that detects the number of branches and slits is also known (Patent Document 1 [Embodiment]). Furthermore, a rotary encoder known as a means for measuring the amount of displacement of an element that is directly displaced by the contact of the detection object such as the upper roller or an element that is indirectly displaced such as the lever (Patent Document) An apparatus using 2) is also known (Patent Documents 3 and 4).

JP2003-294401A JP 2001-227989 A JP 05-32003 JP 07-156503 A

However, since the first device described in the [Prior Art] column of Patent Document 1 is expensive in PSD and needs to be processed with high accuracy so that the upper roller is not warped, Manufacturing cost is extremely high. The second device may erroneously detect the amount of displacement when the photo sensor becomes dirty during use.
In the apparatus described in the [Embodiment] column of Patent Document 1, if the paper thickness to be used is in the range of about 0.05 to 0.3 mm, the paper thickness is specified to be 0.01 mm or less to specify the paper type. Where resolution is required, it is difficult to form slits and branches having a width of 0.01 mm or less. Further, in the devices described in Patent Documents 3 and 4, a disk-shaped scale in which flat surfaces and inclined surfaces are alternately formed in a circumferential direction with a transparent material to form a phase grating is used for the encoder. Cannot be miniaturized, and variation occurs when the scale is assembled.
Therefore, an object of the present invention is to provide a detection device that is excellent in detection accuracy and resolution and that can be miniaturized at low cost.

In order to solve the problem, the detection device of the present invention is:
A device that detects the presence, size, or amount of movement of an object,
A lever portion made of a light-transmitting resin, having a contact that can come into contact with an object, and the contact being displaced with the contact of the object;
A scale part that is integrally formed of the same material as the lever part, can be displaced according to the displacement of the lever part, and in which a large number of light-shielding areas and translucent areas are alternately formed in the displacement direction;
A light source for irradiating the scale with light;
And a light receiver that receives light transmitted through the scale portion.

  According to the detection device of the present invention, when the object comes into contact with the contact of the lever portion, the lever portion is displaced, and the scale portion is displaced according to the displacement. Then, the displacement amount is detected based on the pulse train formed by the light transmitted through the scale portion. Expensive parts such as PSD are not required. Since the scale part can be formed by means such as prism processing, rough surface treatment, printing, etc., the light shielding region and the light transmitting region, these regions can be formed with high accuracy at intervals of 0.01 mm or less, Excellent resolution. Further, since the light receiver only needs to be able to determine the presence or absence of light reception, it will not be erroneously detected even if there is a little cloudiness or dirt. And since the lever part and the scale part are integrally molded, there is no member that relays between the lever part and the scale part, and it is compact, and the relative position between the lever part and the scale part when assembled is from the time of manufacture. There is no fluctuation, and there is little variation with assembly.

The size of the object is, for example, the thickness of the object or the unevenness level of the object surface.
Furthermore, a rotation shaft for supporting the lever portion and the scale portion is provided, and the lever portion and the scale portion extend in different radial directions from the rotation shaft, so that the displacement amount of the scale portion is proportional to that of the contact point. It is possible to improve the detection accuracy. In this configuration, if the lever portion and the scale portion extend in a radial direction that forms an angle other than 180 °, the size can be further reduced.

  In the configuration including the rotating shaft, it is preferable that the rotating shaft further includes a bearing portion that rotatably supports the rotating shaft, and a container that houses the scale portion, the light source, and the light receiver. Since the lever part and the scale part are integrally formed, the container is also small. More preferably, an elastic body that presses the lever portion against the object is provided, and either the lever portion or the scale portion engages with the container and determines the lever portion at a predetermined angle against the restoring force of the elastic body. It has a stopper integrally. As a result, when the object is not present, the stopper is engaged with the container, so that the lever portion is kept at a reference angle, and when the object is present, the restoring force of the elastic body according to the size and the moving amount. This is because the lever portion is displaced against this.

  When the lever portion and the scale portion are formed of different materials, the lever portion and the scale portion are formed of a light transmissive resin so that the scale portion is coupled to the lever portion. For example, the lever portion may be formed of metal, and then the scale portion may be integrally formed with the lever portion, or after both are individually formed, one of the scale portion and the lever portion may be press-fitted into the other.

  Since a detection device that is excellent in detection accuracy and resolution and can be miniaturized can be provided at a low cost, an object can be accurately detected in the supply / discharge process in various machines.

It is the perspective view which looked at the detection apparatus of Embodiment 1 from a certain direction. It is the perspective view similarly seen from another direction. It is the perspective view similarly seen from another direction. It is a vertical direction sectional view parallel to the rotation axis of the detection device. It is a perspective view which shows the inner holder, the connector, and board | substrate which are applied to the same detection apparatus. It is a front view which shows the scale integrated lever applied to the detection apparatus. It is XX sectional drawing of FIG. It is a figure which shows the operation | movement at the time of use of the same detection apparatus. It is a figure which shows the operation | movement at the time of use of the detection apparatus of Embodiment 2. It is a figure which shows the operation | movement at the time of use of the detection apparatus of Embodiment 3. It is sectional drawing which shows the conventional detection apparatus. It is sectional drawing which shows another conventional detection apparatus. It is sectional drawing which shows another conventional detection apparatus.

Embodiment 1
Hereinafter, the present invention will be specifically described based on embodiments. 1 to 3 are perspective views of the detection device of the first embodiment viewed from different directions, FIG. 4 is a vertical sectional view parallel to the rotation axis of the detection device, and FIG. 5 is applied to the detection device. FIG. 6 is a front view showing a scale-integrated lever applied to the detection device.

  The detection device 1 is a device that detects the thickness of a sheet. As shown in FIGS. 1 to 4, the outer holder 2 and the outer holder are provided with a main component storage space that protrudes upward in a substantially cross shape in plan view. 2 includes a circuit board 3, a light receiving element 4, a collimating lens 5, a light emitting element 6 and a scale-integrated lever 7 fixed to the lower surface.

  The scale-integrated lever 7 is entirely made of a light-transmitting resin. As shown in FIG. 6, the lever portion 71, the scale portion 72, the rotating shaft 73, and the stopper 74 are about 1.3 mm thick except for the rotating shaft 73 portion. It is integrally formed into a plate shape. The outline of the scale-integrated lever 7 has two sides a and b that are orthogonal to each other when viewed from the front, a side c that is parallel to one side a and shorter than side a among these two sides, and an oblique line that connects side a and side c. It forms a substantially trapezoid consisting of the side d. A lever portion 71 is formed so as to extend substantially along the side d at a corner where the side a and the side d intersect, and a stopper 74 so as to extend along the side c at a corner where the side b and the side c intersect. Is formed. The peripheral surface of the lever portion 71 is smoothly bent so as to be away from the extension line of the side d and approach the side b as it goes toward the tip, and forms a contact point with the sheet to be detected.

  The rotating shaft 73 has a cylindrical shape that protrudes at an intermediate portion of the side d so as to be orthogonal to both surfaces of the plate-like portion. Therefore, the lever portion 71 and the stopper 74 are substantially diagonal to each other with the rotation shaft 73 therebetween. Further, in the vicinity of the corner where the side a and the side b intersect, a scale portion 72 composed of a large number of light-shielding regions and light-transmitting regions arranged alternately at equal intervals in the circumferential direction around the rotation shaft 73 is formed. Has been. As a means for providing the scale portion 72, as shown in FIG. 7 as an XX sectional view of FIG. 6, a horizontal smooth surface as a light transmitting region 72a formed on one main surface of the plate-like portion and a light shielding region 72b. It is also possible to use a prism (FIGS. 7A and 7B) composed of a non-horizontal smooth surface, or to print a light shielding material or roughen the surface next to the horizontal smooth surface as the translucent region 72a. Thus, the light shielding region 72b (FIG. 7C) may be used.

  The rotary shaft 73 is supported by the bearing portion 21 at the upper end of the outer holder 2 so that the lever portion 71 is on the upper side and the scale portion 72 is on the lower side. A coil spring 75 is attached to the outer peripheral surface of the rotating shaft 73 to exert a restoring force in a direction in which the rotating shaft 73 is urged upward. The restoring force is suppressed by engaging the stopper 74 with the outer holder 2, and the line connecting the contact point of the lever portion 71 and the rotary shaft 73 is maintained at an inclination of approximately 30 degrees with respect to the horizontal. I'm leaning. The translucent area 72a or the light-shielding area 72b at both ends of the scale portion 72 is at a position rotated by 100 to 150 degrees from this line.

  A U-shaped inner holder 8 and a connector 31 are mounted on the circuit board 3 as shown in FIGS. 4 and 5, the light receiving element 4 on one side of the inner holder 8, and the lens 5 and the light emitting element on the other side. 6 is stored. A positioning boss hole 32 is formed at the end of the circuit board 3 on the opposite side of the connector 31 with the inner holder 8 in between, and a boss (not shown) of the outer holder 2 is fitted into the boss hole 32 so that the scale portion The position of the inner holder 8 with respect to the outer holder 2 is determined so that 72 faces the lens 5. The lower surface of the circuit board 3 is covered with a cover 33.

  The detection device 1 is formed at the end of the outer holder 2 opposite to the connector 31 by fitting the two positioning bosses 22 and 22 formed on both sides of the lower surface of the outer holder 2 into the positioning boss holes of the printing machine. A set screw is screwed into the screw hole 23 and the screw hole of the printing machine to be used by being fixed to the printing machine.

  FIG. 8 is a diagram illustrating an operation when the detection apparatus 1 is used. When there is no sheet and the highest position of the lever portion 71 is in contact with the reference plane (the position indicated by the solid line in the figure), the highest position of the lever portion 71 is lowered by Δt by being pushed by the supplied paper K. (A dashed line position in the figure). The length from the highest position of the lever portion 71 to the center of the rotating shaft 73 is L, the angle of the lever portion 71 at that time is θ, and the length from the center of the rotating shaft 73 to the optical axis center of the scale portion 72 is Is J, and a small displacement amount of the scale portion 72 accompanying the displacement of the lever portion 71 is Δd. By designing so that the highest position of the lever portion 71 always exists on one perpendicular line V with respect to the reference plane as much as possible, L: Δt / cos θ = J: Δd, and Δt = Δd (1 / J) Lcos θ is derived. The length from the highest position of the lever portion 71 to the center of the rotation shaft 73 and the angle of the lever portion 71 with respect to the horizontal are both variables, but cos θ increases as L decreases with the decrease in the highest position of the lever portion 71. So they cancel each other out. Therefore, (1 / J) L cos θ maintains a substantially constant value. As a result, Δt and Δd are proportional.

  According to this detection device 1, when a sheet supplied by a supply roller (not shown) comes into contact with the contact of the lever portion 71, the lever portion 71 is displaced, and the scale portion 72 is displaced in proportion to the displacement amount. To do. The light emitted from the light emitting element 6 and transmitted through the light transmitting region of the scale portion 72 is received by the light receiving element 4. Even if the surface of the light receiving element 4 is slightly clouded or dirty, there is no problem as long as light can be received. The light receiving element 4 has 2 channels built in, and when the pitch between the light transmitting region 72a and the light shielding region 72b is 0.0423 mm, a pulse signal with a resolution of 0.0053 mm is output by multiplying by 8. Since the lever portion 71 and the scale portion 72 are integrally formed, there is no member that relays between the lever portion 71 and the scale portion 72, and the lever portion 71 and the scale portion 72 are not assembled when assembled. The relative position does not change from the time of manufacture, and there is little variation associated with assembly. It is only necessary to supply the supply roller, and it is not necessary to finish the surface with high accuracy.

Embodiment 2
In the detection device of the second embodiment, as shown in FIG. 9, the object moving in the vertical direction can be detected by making the angle between the lever portion 71 and the scale portion 72 larger than 180 °. . In this case, it is only necessary to replace the scale integrated lever 7 with that of the first embodiment.

Embodiment 3
As shown in FIG. 10, the detection device of the third embodiment has the moving direction of the object substantially coincident with the displacement direction of the lever portion 71 and is suitable for detecting the moving speed of the object.

DESCRIPTION OF SYMBOLS 1 Detection apparatus 2 Outer holder 3 Circuit board 4 Light receiving element 5 Lens 6 Light emitting element 7 Scale integrated lever 71 Lever part 72 Scale part 73 Rotating shaft 74 Stopper 75 Coil spring

Claims (14)

A device that detects the presence, size, or amount of movement of an object,
A lever portion made of a light-transmitting resin, having a contact that can come into contact with an object, and the contact being displaced with the contact of the object;
A scale part that is integrally formed of the same material as the lever part, can be displaced according to the displacement of the lever part, and in which a large number of light-shielding areas and translucent areas are alternately formed in the displacement direction;
A light source for irradiating the scale with light;
A detection device comprising: a light receiver that receives light transmitted through the scale unit.   The detection apparatus according to claim 1, wherein the size of the object is a thickness of the object or an unevenness level of the object surface.   The detection device according to claim 1, further comprising a rotation shaft that supports the lever portion and the scale portion, wherein the lever portion and the scale portion extend in different radial directions from the rotation shaft.   The detection device according to claim 3, wherein the lever portion and the scale portion extend in a radial direction that forms an angle other than 180 °.   The detection device according to claim 3, further comprising a bearing portion that rotatably supports the rotation shaft, and a container that houses the scale portion, the light source, and the light receiver.   Furthermore, an elastic body that presses the lever portion against the object is provided, and either the lever portion or the scale portion engages with the container and determines the lever portion at a predetermined angle against the restoring force of the elastic body. The detection device according to claim 5, which has a stopper integrally.   The detection device according to claim 1, wherein the light shielding region is formed by one or more means selected from prism processing, rough surface processing, and printing. A device that detects the presence, size, or amount of movement of an object,
A lever portion having a contact capable of abutting against an object, wherein the contact is displaced as the object abuts;
A scale portion formed of a light-transmitting resin so as to be coupled to the lever portion, displaceable in accordance with the displacement of the lever portion, and a plurality of light-shielding regions and light-transmitting regions formed alternately in the displacement direction;
A light source for irradiating the scale with light;
A detection device comprising: a light receiver that receives light transmitted through the scale unit.   The detection device according to claim 8, wherein the size of the object is a thickness of the object or a level of unevenness on the surface of the object.   The detection device according to claim 8, further comprising a rotation shaft that supports the lever portion and the scale portion, wherein the lever portion and the scale portion extend in different radial directions from the rotation shaft.   The detection device according to claim 10, wherein the lever portion and the scale portion extend in a radial direction that forms an angle other than 180 ° with respect to each other.   The detection device according to claim 10, further comprising a bearing portion that rotatably supports the rotating shaft, and a container that houses the scale portion, the light source, and the light receiver.   Furthermore, an elastic body that presses the lever portion against the object is provided, and either the lever portion or the scale portion engages with the container and determines the lever portion at a predetermined angle against the restoring force of the elastic body. The detection device according to claim 12, which has a stopper integrally.   The detection device according to claim 8, wherein the light shielding region is formed by one or more means selected from prism processing, rough surface processing, and printing.

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