JP2544047B2 - Optical displacement measuring device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention can measure the amount of displacement by detecting the optical signal reflected from an object by irradiating the object with a light beam such as a laser beam and detecting the received light signal with a position detecting element. To the improvement of the optical displacement measuring device.

[0002]

2. Description of the Related Art As shown in FIG. 4, an optical displacement measuring device of this type includes an optical head 100 and a controller 200.
Are connected via a signal line 300, and the optical head 100 is provided with a light projecting section 101 and a light receiving section 102. The light projecting portion 101 of the optical head 100
Includes a projection lens 100a, a laser light emitting element 100b,
The light emitting element drive circuit 100e is built in, and the light receiving unit 1
Reference numeral 02 designates a light receiving lens 100c, a position detecting element 100d serving as a light receiving element, and an I / V for converting a position detecting signal output from the position detecting element 100d in the form of current into a voltage signal.
The conversion circuit 100f is built in.

In such an optical displacement measuring apparatus, if the light emitting element drive circuit 100e of the light emitting section 101 is driven by the modulated pulse from the oscillator 202 provided in the controller 200, the laser light emitting element 100b is obtained. A modulated laser beam is emitted toward the object OB, and the reflected light reflected from the object OB is received by the light receiving unit 10.
When the second position detecting element 100d receives light, the position detecting element 100d outputs two current values I1 and I2. Therefore, the current values I1 and I2 are converted into voltage signals V1 and V2. After that, if the signal processing unit 201 in the controller 200 performs arithmetic processing based on the triangulation method, the displacement amount of the optical head 100 from the reference value can be output as distance measurement data.

However, when such a displacement measuring device is used, the light amount of the reflected light received by the light receiving portion 102 of the optical head 100 is different depending on the material, color, etc. of the object, so that the light receiving amount is always constant. There is a light-receiving gain adjustment function that automatically adjusts to an optimum value, but such a light-receiving gain adjustment function does not adopt a method of continuously changing it in order to facilitate control by a microcomputer. It is customary to use many things that change in stages. However, in general, when the light receiving gain is changed, the circuit operation becomes unstable when the light receiving gain is changed. Therefore, it is desirable to suppress the change of the light receiving gain to a necessary minimum. Also, the light-receiving gain changes depending on the object, so if the measurement situation is taken into consideration, the light-receiving gain can be adjusted fully automatically, semi-automatically, or manually if necessary. It is desirable to be able to select it according to.

[0005]

DISCLOSURE OF THE INVENTION The displacement measuring apparatus of the present invention has been made in view of such circumstances, and the light receiving gain of the optical head is always set to the light receiving gain after the operation of the light receiving gain mode key. Fully automatic adjustment mode that allows automatic adjustment to the optimum value, semi-automatic adjustment mode that detects the amount of received light at the time when the light receiving gain mode key is operated and sets the light receiving gain to the optimum value at that time, the light receiving gain is optimized by the user side From among the manual adjustment modes for selecting and setting values,
It is an object of the present invention to provide an optical displacement measuring device capable of selectively setting any mode.

The optical displacement measuring device according to claim 1 is
An optical head provided with a light projecting unit for irradiating an object with light and a light receiving unit for receiving light reflected by the object, and an optical head connected to the optical head via a signal line. Optical displacement constituted by combining an arithmetic processing means for arithmetically processing a displacement amount according to a position detection signal output from the controller and a controller for displaying and outputting distance measurement pair data arithmetically processed by the arithmetic processing device. In the measuring device, the controller has a light-receiving gain variable circuit that varies a light-receiving gain of a light-receiving signal received by a light-receiving unit of the optical head, and the light-receiving gain is selectively set in an automatic adjustment mode, a semi-automatic adjustment mode, and a manual adjustment mode. The light receiving gain mode selection means having a light receiving gain mode selection setting switch and the light receiving gain mode selection setting switch are operated to select and set. A signal processing unit for controlling the light-receiving gain variable circuit according to the selected mode, and if the automatic adjustment mode is selected by the light-receiving gain mode selection setting switch, the light is reflected from the object and received by the optical head. The two position detection signals detected by the unit are added by the arithmetic processing device, and the amount of light received by the optical head is determined by the magnitude of the added value,
In accordance with the result of the determination, even if the optical head and / or the object moves during the distance measurement by automatically controlling the light receiving gain variable circuit, the light receiving gain of the optical head is always kept. When the semi-automatic adjustment mode is selected, the automatic adjustment mode is set only while the light receiving gain mode selection setting switch is operated, and the light receiving gain of the optical head is optimized. If the value is controlled to a certain value and the operation of the light receiving gain mode selection switch is stopped, while the distance measurement of the object is interrupted during that time, when the manual adjustment mode is selected, the light receiving gain mode selection setting switch is set. It is characterized in that the light receiving gain of the optical head can be manually set by operating. An optical displacement measuring device according to a second aspect is the optical displacement measuring device according to the first aspect, in which the light receiving amount lighting means for displaying the display of the light receiving amount by moving the lighting position and the light receiving gain are optimized. An up / down key provided for setting a value and an enter key provided for storing the light receiving gain set by the up / down key are further provided, and the lighting position of the light receiving amount lighting means is checked. However, the light receiving gain can be set to an optimum value by operating the enter key when the up / down key is operated to select the light receiving gain to an optimum value.

[0007]

According to the optical displacement measuring device of the present invention, the light-receiving gain of the optical head can be selected from the fully automatic adjustment mode, the semi-automatic adjustment mode and the manual adjustment mode according to the reflecting surface of the object and the skill level of the user. From, you can select and set any mode. Here, in the fully automatic adjustment mode, since the light receiving gain variable circuit is always activated, even if the optical head is moved and the optical head or the object moves during the distance measurement,
It is possible to fully automatically control the light-receiving gain of the optical head to control it to an optimum value. Such a fully automatic adjustment mode is suitable for a beginner user who has difficulty in performing optimum light receiving gain control. Further, in the semi-automatic adjustment mode, the light receiving gain at the time when the selection setting switch is operated can be controlled to an optimum value. Such a semi-automatic adjustment mode does not require measurement on a part of the object and there is a part with extremely different reflectance, so if you execute only the necessary part, measurement with different reflectance is unnecessary. The part can be ignored and stable distance measurement becomes possible. Furthermore,
In the manual adjustment mode, the user can set an arbitrary light receiving gain, which is particularly suitable for a user who is familiar with distance measurement.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the optical displacement measuring device of the present invention will be described below with reference to the accompanying drawings. 1 is a block diagram of a main part of the device of the present invention, FIG. 2 is an external view of the optical displacement measuring device of the present invention, and FIG. 3 is an external view of a front panel 10A of a controller 10 of the optical displacement measuring device of the present invention. The parts corresponding to those of the conventional device shown in FIG. 4 are denoted by the same reference numerals and the description thereof will be omitted. The configuration will be described below with reference to FIG. The optical displacement measuring device includes an optical head 10
0 and the controller 10 are connected via a signal line 300. The controller 10 includes a signal processing unit 20, a display unit 11, light receiving gain mode keys Sa, Sb, Sc as a light receiving gain mode selection setting switch, and an oscillator 202. Of these, the signal processing unit 20 is configured to include a CPU 25, and the position detection signals V1 and V2 output by converting the current signals I1 and I2 into voltage signals from the optical head 100 are output to the amplifier 2.
After being amplified to a predetermined level by 2, the detection circuit 23
At position, the detected position detection signals V1 and V2 are detected in synchronization with the oscillation signal output from the oscillator 202, and the detected position detection signals V1 and V2 are converted into digital signals by the A / D converter 24.
The PU 25 performs arithmetic processing to obtain distance measurement data. The distance measurement data thus obtained is displayed on the display unit and
The A / A converter 26 converts the analog signal and outputs the analog signal to the outside through an output terminal. Further, the key sense circuit 28 determines the operation of the operation switches including the light receiving gain mode selection setting switch,
The display drive circuit 27 receives the control signal from the CPU 25 and drives the display unit 11. Further, in this embodiment, the amount of light received by the light receiving unit 102 of the optical head 100 is detected by the position detection signals V1 and V2 calculated by the CPU 25.
The gain of the amplifier 22 is controlled by operating the light receiving gain variable circuit 21 according to the determination result of the CPU 25 at this time. It is desirable that such a light receiving gain variable circuit 21 be capable of controlling the gain of the amplifier 22 steplessly. However, in the case of configuring a simple control system with good response, a plurality of preset gain values are set. You may make it a structure which changes sequentially and increases / decreases. Next, the front panel 10A of the controller 10 will be described based on FIG. Light receiving gain mode key Sa, Sb, Sc
Selects the light-receiving gain mode. When the mode of the pressed key is selected, the LED (S
Any one of d, Se, and Sf) lights up. The light receiving gain LED 11d displays the current light receiving gain at the lighting position. In the manual adjustment mode, by pressing the enter key 11b, the light receiving gain LED 11d changes from blinking to lighting and the light receiving gain is fixed. The light-receiving amount LED 11c displays the current light-receiving amount by moving the lighting position with reference to the total light-receiving amount that can be obtained by the current light-receiving gain. DARK lights up. The numerical value display LED 11f displays the measured value and each set value. The up / down key 11a is used to match the set value, and by pressing the enter key 11b, the set value is confirmed and input. The unit display lamp 11e lights and displays the unit of the numerical value displayed on the numerical display LED 11f.

Next, the operation will be described with reference to FIG. According to the optical displacement measuring device of the present invention, the light receiving gain of the optical head 100 is selected from the fully automatic adjustment mode, the semi-automatic adjustment mode, and the manual adjustment mode according to the reflection surface of the object and the skill level of the user. Any mode can be selected and set. Here, in the fully automatic adjustment mode, the light receiving gain mode key S
When a (AUTO) is operated, the position detection signals V1 and V2 converted into voltage signals and output from the optical head 100 are output.
Is amplified to a predetermined level, detected by the detection circuit 23 in synchronization with the oscillation signal of the oscillator 202, converted into a digital signal by the A / D converter 24, and then processed in the CPU 25. The CPU 25 determines the amount of received light detected by the optical head 100 based on whether the value obtained by adding the position detection signals V1 and V2 is large or small, and is provided on the front panel 10A of the controller 10 according to the determination result. The lighting position of the light receiving amount LED 11c is moved (see FIG. 3), and the light receiving gain variable circuit 21 is controlled according to the determination result at that time,
Adjust the gain of the amplifier 22. As a result, while the light receiving gain variable circuit 21 is in operation, the optical head 10
Even when 0 is activated and the distance is being measured, the amount of received light is always controlled to an optimum value (fully automatic adjustment mode). Further, in the semi-automatic adjustment mode, only when the light receiving gain mode key Sb (SEMI) is operated, the above-mentioned fully automatic adjusting mode is set, and the light receiving gain is controlled to the optimum. Such a semi-automatic adjustment mode does not require measurement on a part of the object and there is a part with extremely different reflectance, so if you execute only the necessary part, measurement with different reflectance is unnecessary. The part can be ignored and stable distance measurement becomes possible. For example, it is suitable when a portion other than the screw hole of the motor shaft in which the screw hole is formed is used as a reflecting surface. On the other hand, in the manual adjustment mode, the light receiving gain can be set by operating the light receiving gain mode key Sc (MANU).
In this case, the received light amount is displayed by moving the lighting position of the received light amount LED 11c, and therefore the operator can operate the up / down key 11a while viewing the display to select the optimum received light gain. By pressing 11b, the selected light receiving gain is set.

[0010]

According to the optical displacement measuring device of the present invention,
The light-receiving gain of the optical head can be selected and set from fully automatic adjustment mode, semi-automatic adjustment mode, and manual adjustment mode, so optimum gain control can be performed according to the reflecting surface of the object and user's skill level. You can choose and it is very convenient.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of a device of the present invention.

FIG. 2 is a perspective view showing an appearance of an optical displacement measuring device of the present invention.

FIG. 3 is an explanatory diagram showing an appearance of a front panel of a controller of the optical displacement measuring device of the present invention.

FIG. 4 is a block diagram showing an internal configuration of a conventional optical displacement measuring device.

[Explanation of symbols]

 10 ... Controller 10A ... Front panel 11 ... Display unit 20 ... Signal processing unit 21 ... Light receiving gain variable circuit 22 ... Amplifier 23 ... Detection circuit 24 ... A / D Converter 25 ... CPU 26 ... D / A converter 27 ... Display drive circuit 28 ... Key sense circuit 100 ... Optical head 202 ... Oscillator 300 ... Signal line Sa, Sb , Sc ・ ・ ・ Light receiving gain mode key Sd, Se, Sf ・ ・ ・ LED of light receiving gain mode key

Front page continuation (72) Inventor Yoshihiko Sugimoto 1048 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works, Ltd. (56) References JP-A 1-220214 (JP, A) JP 58-172938 A) JP 63-236916 (JP, A) JP 59-87501 (JP, A) JP 3-80301 (JP, A) JP-B 2-333337 (JP, B2)

Claims (2)

(57) [Claims] 1. An optical head including a light projecting unit for irradiating an object with light, and a light receiving unit for receiving light reflected by the object, and a signal line to the optical head. A combination of an arithmetic processing unit that is connected and arithmetically processes a displacement amount according to a position detection signal output from the optical head, and a controller that displays and outputs distance measurement pair data arithmetically processed by the arithmetic processing device. In the optical displacement measuring device described above, the controller includes a light-receiving gain variable circuit that varies the light-receiving gain of the light-receiving signal received by the light-receiving section of the optical head, and the light-receiving gain is automatically adjusted in the mode of semi-automatic adjustment, manual adjustment. A light receiving gain mode setting means having a light receiving gain mode selection setting switch for selectively setting a mode, and an operation of the light receiving gain mode selection setting switch. And a signal processing unit for controlling the light receiving gain variable circuit according to the mode that is selectively set, and if the automatic adjustment mode is selected by the light receiving gain mode selection setting switch, it is reflected from the object, The two position detection signals received by the light receiving section of the optical head are added by the arithmetic processing unit, and the amount of light received by the optical head is discriminated according to the magnitude of the added value. Therefore, even if the optical head and / or the object moves during the distance measurement by automatically controlling the light receiving gain variable circuit, the light receiving gain of the optical head is always controlled to an optimum value. If the semi-automatic adjustment mode is selected, the automatic adjustment mode is set only while the light receiving gain mode selection setting switch is operated, If the light receiving gain of the head is controlled to an optimum value and the operation of the light receiving gain mode selection switch is stopped, the distance measurement of the object is interrupted during that time, while the light receiving gain is selected when the manual adjustment mode is selected. An optical displacement measuring device, characterized in that a light receiving gain of the optical head can be manually set by operating a gain mode selection setting switch. 2. A light receiving amount lighting means for displaying a light receiving amount display by moving a lighting position, an up / down key provided for setting and operating a light receiving gain to an optimum value, and set by the up / down key. Further includes an enter key provided to store the received light gain, and when the up / down key is operated to select the optimum light receiving gain while observing the lighting position of the light receiving amount lighting means, 2. The light receiving gain can be set to an optimum value by operating the enter key.
The optical displacement measuring device described in.