JP2000065602A - Pulse-generating device utilizing shielding sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulse-generating device used for correctly grasping the number of revolutions and an angle of rotation of a rotary body or a movement distance of a belt or the like moved by the rotary body. SOLUTION: This is a pulse-generating device for detecting the number of revolutions and an angle of rotation of a rotary body, which includes a pulse plate 11 rotating while coupled to the rotary body and a shielding sensor comprising a light-emitting element 12 and a photodetecting element 13 arranged opposite to each other via the pulse plate 11. The pulse plate 11 has slits 11a extending radially from a rotation center with a predetermined circumferential pitch. A detection light emitted from the light-emitting element 12 and detected by the photodetecting element 13 is irradiated to a position where the slits 11a of the slit plate 11 can be detected. A circumferential width of the slit 11a formed in the pulse plate 11 is set smaller than a circumferential width of a non-slit part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulse generator using a shielding sensor, and more particularly, to accurately grasp the number of rotations and the rotation angle of a rotating body, or the moving distance of a belt or the like run by the rotating body. To a pulse generator used for the purpose.

[0002]

2. Description of the Related Art As means for measuring the number of rotations and the rotation angle of a rotating body which is driven to rotate by a motor or the like, and for measuring a belt traveling by the rotating body and a transport distance of an object carried by the rotating body, etc. Conventionally, a pulse generation device using a shield sensor has been used. This type of pulse generating apparatus uses a pulse generating apparatus, for example, as shown in FIG. 2 (a), in order to correlate the number of rotations of a motor with the position of an object to be conveyed by a belt in a conveying apparatus using a belt as shown in FIG. It is linked to the axis. More specifically, the transport device 1 includes a driving-side first belt 3 stretched by rollers 2a and 2b, and rollers 4a and 4b.
And a motor 7 for rotating the drive roller 2 a via a force transmission belt 6. The two endless belts 3, 5 are arranged in parallel so that the opposing running surfaces are close to each other, and a conveyed object (for example, a bill, a card, a coin) is sandwiched between the two adjacent running surfaces. Carry in a certain direction. FIG.
FIG. 2B is a configuration diagram of a pulse generating device provided in the transfer device. The pulse generating device 10 has a substantially circular pulse plate 1 whose axis is fixed by the other output shaft 7 b of the motor 7.
1 and a light-emitting element 1 disposed oppositely with a pulse plate 11 interposed therebetween.
2 and a light receiving element 13 and a control unit 14 for inputting a light receiving signal from the light receiving element.

The pulse plate 11 has slits 11a extending radially from the center thereof at a predetermined circumferential pitch. As shown in FIG. 3C, the circumferential width of the slit 11a and the circumferential width of the non-slit portion 11b are provided. Are set in advance to be 1: 1. Light receiving 1 emitted from light emitting element 12
The detection light received by 3 is applied to a position where the slit 11a or the non-slit portion 11b can be detected. The control unit 14 obtains a waveform as shown in (d) based on the transmission time of the detection light passing through the slit 11a or the shielding time during which the non-slit 11b shields the detection light. As shown in (d), despite the fact that the width of the slit 11a and the width of the non-slit portion 11b are set to 1: 1, the obtained pulse width is such that the “bright” time t1 is “dark”. It is longer than time t2. This phenomenon occurs even when the pulse plate is rotated at a constant speed, and such a phenomenon is caused when a part of the detection light leaks to the non-slit portion side when the detection light passes through the slit 1a. It is presumed to be due to For this reason, in the conventional pulse generation device, it is impossible to use both the rising and falling of one pulse as a timing signal, and only one of the rising and falling of each pulse is used as a timing signal. It was used as a signal. For this reason, in the conventional pulse generation device, in order to secure a sufficient resolution, the output shaft 7 of the motor is required.
It is necessary to adopt a method of rotating the pulse plate at high speed through a gear without directly connecting b to the pulse plate 11, or a method of increasing the number of slits of the pulse plate. However, the former method increases the number of parts, complicates the configuration, increases the size,
The latter method has a disadvantage that the cost is increased, and the latter method requires more labor for slit processing.

[0004]

The problem to be solved by the present invention is to use for accurately grasping the rotation speed and rotation angle of a rotating body, or the moving distance of a belt or the like run by the rotating body. A pulse generation device is provided. Specifically, when rotating a pulse plate provided with slits formed at a predetermined pitch in the circumferential direction, the position corresponding to the slit is irradiated with the detection light to correspond to the slit width and the width of the non-slit part. In the pulse generation device which obtains a pulse waveform to be obtained, based on the obtained data about each width, the pulse generation device is configured to detect the relationship between the number of rotations of the motor and the position of the transferred object or the like conveyed by the rotating body or the like. When a part of the detection light irradiated into the slit wraps around the non-slit part side, the width a of the “bright” part and the width b of the “dark” part are a
> B. More specifically, the present invention provides a pulse generation device that does not involve the disadvantages of a conventional pulse generation device, such as a complicated configuration that is necessarily required to increase the resolution, an increase in size, and an increase in cost. is there.

[0005]

According to one aspect of the present invention, there is provided a pulse generating apparatus for detecting the number of rotations and a rotation angle of a rotating body, wherein the pulse generating apparatus is connected to the rotating body and rotates. A pulse plate, and a shielding sensor including a light emitting element and a light receiving element arranged to face each other across the pulse plate,
The pulse plate has slits extending radially from the center of rotation at a predetermined circumferential pitch, and irradiates detection light emitted from the light emitting element and received by the light receiving element to a position where the slit of the pulse plate can be detected. In the above configuration, the circumferential width of the slit formed in the pulse plate is smaller than the circumferential width of the non-slit portion. According to a second aspect of the present invention, the pulse width obtained from the detection light received by the light receiving element has a light-to-dark ratio by configuring the circumferential width of the slit formed in the pulse plate to be smaller than the circumferential width of the non-slit portion. Is 1: 1.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to embodiments shown in the drawings. The description will be made with reference to FIG. 2 as well, and the same parts as those in FIG. FIG. 1 (a) is a diagram showing a main configuration of an example of the pulse plate of the present invention. The characteristic configuration of the present invention is that the width a of the slit 11a of the pulse plate 11 is larger than the width b of the non-slit portion 11b. The point is that it is set small. That is, as shown in FIG.
A pulse plate 11 that is connected to a rotating shaft 7a of the rotating body and rotates, and a light-emitting element that is opposed to the pulse plate 11 with the pulse plate 11 interposed therebetween. And a shielding sensor comprising a light receiving element 12 and a light receiving element 13. The pulse plate 11 has slits 11 a extending radially from the rotation center at a predetermined circumferential pitch, and can detect the detection light emitted from the light emitting element 12 and received by the light receiving element 13 through the slit 11 a of the pulse plate 11. It is configured to irradiate the position. In such a pulse generation device, the slit 11 formed in the pulse plate 11
By setting the circumferential width a of a to be smaller than the circumferential width b of the non-slit portion 11b, the ratio of the time width of light and dark received by the light receiving element 13 (light-dark ratio) can be set to be equal. It becomes possible.

FIG. 1B shows a pulse waveform generated by the control unit 14 based on data obtained from the light receiving device 13 in the pulse generating apparatus using the pulse plate shown in FIG. And the non-slit portion 11
The relationship between b and the circumferential width b is set so that a <b, and the time width of “bright” and “dark” (light-dark ratio of pulse)
Are set in advance such that the ratios are 1: 1. Therefore, a timing signal can be obtained from both the rising and falling edges of each pulse, and a high resolution can be secured from the beginning. The ratio between the width a of the slit 11a and the width b of the non-slit portion 11b is usually determined experimentally. In other words, when the width of the slit and the width of the non-slit portion are set to be equal to each other as in the related art, since the width of “bright” becomes large due to the wraparound of the detection light, both the rising and falling of the pulse are used. The timing signal could not be obtained and the resolution was low. In order to increase the resolution, it was necessary to increase the number of rotations of the pulse plate or increase the number of slits of the pulse plate.
This is a problem because it causes disadvantages such as an increase in size, an increase in cost, and an increase in the number of steps for processing the pulse plate. On the other hand, in the present embodiment, the width a of the slit 11a and the width b of the non-slit 11b are based on the results obtained by experiments and the like.
By setting the ratio to a predetermined value in advance, the light-to-dark ratio of the pulse generated by the pulse generator is set to 1: 1. Therefore, it is possible to obtain a timing signal based on both the rising portion and the falling portion of the obtained pulse.
This eliminates the need for complicated operations and an increase in the number of slits.

[0008]

As described above, according to the present invention, there is provided a pulse generating apparatus used for accurately grasping the number of rotations and the rotation angle of a rotating body, or the moving distance of a belt or the like run by the rotating body. Can be provided. Specifically, when rotating a pulse plate provided with slits formed at a predetermined pitch in the circumferential direction, the position corresponding to the slit is irradiated with the detection light to correspond to the slit width and the width of the non-slit part. In the pulse generation device which obtains a pulse waveform to be obtained, based on the obtained data about each width, the pulse generation device is configured to detect the relationship between the number of rotations of the motor and the position of the transferred object or the like conveyed by the rotating body or the like. By preventing a part of the detection light irradiated into the slit from wrapping around the non-slit part, the width a of the “bright” part and the width b of the “dark” part do not satisfy a> b. More specifically, it is possible to provide a pulse generation device that does not involve a problem such as a complicated configuration, an increase in size, and an increase in cost that are necessarily required to increase the resolution in a conventional pulse generation device. it can.

[Brief description of the drawings]

FIGS. 1A and 1B are a main part configuration diagram of a pulse plate constituting a pulse generation device according to an embodiment of the present invention, and a diagram showing an obtained pulse waveform.

FIGS. 2 (a), (b), (c) and (d) are an overall configuration diagram, a main configuration diagram, a main configuration diagram of a pulse plate, and a configuration diagram of an obtained pulse waveform of a conventional pulse generator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Conveying device, 2a, 2b roller, 3 first belt, 4a, 4b roller, 5 second belt, 6 force transmission belt, 7 motor, 7a, 7b output shaft, 10 pulse generator, 11 pulse plate, 11a Slit, 1
1b Non-slit part, 12 light emitting element, 13 light receiving element, 14 control part.

Claims (2)

[Claims] 1. A pulse generator for detecting the number of rotations and the rotation angle of a rotating body, comprising: a pulse plate connected to the rotating body and rotating; and a light emitting element opposed to the pulse plate with the pulse plate interposed therebetween. And a shielding sensor comprising a light receiving element,
The pulse plate has slits extending radially from the rotation center at a predetermined circumferential pitch, and irradiates detection light emitted from the light emitting element and received by the light receiving element to a position where the slit of the pulse plate can be detected. A pulse generator using a shielding sensor, wherein a circumferential width of a slit formed in the pulse plate is smaller than a circumferential width of a non-slit portion. 2. The method according to claim 1, wherein the width of the slit formed in the pulse plate in the circumferential direction is smaller than the width of the non-slit portion in the circumferential direction. 2. The pulse generation device using the shielding sensor according to claim 1, wherein the ratio is set to 1: 2.