JPH0352882B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a detection object that allows the mark position to be detected without adjustment, without being affected by the ground color, the type of coloring of the mark, color difference, etc. Regarding the non-adjustable body mark detection device, it is suitable for use, for example, in detecting a fitting mark attached to a tube container to seal the bottom of the tube container by crimping and stopping the rotation at a predetermined position. This invention relates to a non-adjustable body mark device.

[Prior art]

Cosmetics, toothpaste, etc. are generally used in flexible tube containers, but in order to manufacture cosmetics, etc. in tube containers, it is necessary to make sure that the product name, etc. is in the correct position. The bottom must be crimp-sealed in place.

For this purpose, first, as shown in FIG. 3, a cylindrical container body 1 with an open bottom is closed with a lid 2. next,
The container body 1 is placed on a holder and rotated, the position of the alignment mark 3 attached to the bottom of the container body 1 is detected by a mark sensor, and the holder is stopped at a predetermined position. Next, cosmetics and the like are filled into the container body 1 from the bottom. Furthermore, as shown in FIG. 4, the bottom part is crimped by a crimping means to form the sealing part 4, so that the sealing part 4 is formed with the alignment mark 3 in the center. be done.

However, the container body 1 is often colored as desired for each product, and the background color of the container body 1 varies from white to red, black, etc., and the matching mark 3 also has a color that is different from the above-mentioned background. Various colors are applied to match the coloring. As a result, when the background color is bright and the matching mark 3 is dark, the detection signal by the mark sensor becomes as shown in waveform characteristic 5 shown in Fig. 5; conversely, when the background color is dark and the matching mark 3 is bright, In this case, the detected signal has a waveform characteristic 6 shown in FIG. In this way, the container body 1 and the matching mark 3 are colored in various ways for each product, so the color difference between the container body 1 and the matching mark 3 varies from product to product, but It is also necessary to be able to accurately detect the position of the match mark 3.

Therefore, in the prior art, as shown in FIG. 7, an adjustable mark detection device for a detected object is known.

That is, in FIG. 7, 11 is a stepping motor, and the rotation of the stepping motor 11 is transmitted to a rotating shaft 13 via a belt 12. Reference numeral 14 denotes a holder attachment/detachment device provided on the rotating shaft 13, and the holder attachment/detachment device 14 is configured to automatically attach/detach a holder 15, which will be described later, by, for example, magnetic means. Reference numeral 15 denotes a holder that is transported by a transport means (not shown) such as a conveyor or a turntable, and the container main body 1 shown in FIG. 3 is placed on the holder 15 with the bottom facing upward. and,
When the holder 15 reaches the position of the holder attaching/detaching device 14, it is magnetically attached to the holder attaching/detaching device 14 and rotated by the stepping motor 11. When the stepping motor 11 is stopped upon detection of the match mark 3, the holder attaching/detaching device 14 is rotated by the stepping motor 11. The material is detached without rotation and transported again to the next process by the transport means.

Reference numeral 16 denotes a photoelectric sensor for detecting the alignment mark 3. For example, a host transistor, a host diode, or the like is used as the photoelectric sensor 16, and outputs a detection signal as shown in FIGS. 5 and 6. 17 is an amplification circuit that amplifies the detection signal from the photoelectric sensor 16;
18 is an inversion circuit for peak value inversion provided at the next stage of the amplifier circuit 17, and 19 is a ground color changeover switch that outputs an inversion signal to the inversion circuit 18, and this switch 19 is attached to the container body 1. When the peak value of the detection signal falls due to coloring (in the case of Figure 5),
The configuration is such that an inversion signal is manually output in advance in order to invert the peak value of the detection signal, and when the peak value rises as shown in FIG. 6, no switching operation is performed.

20 is a comparison circuit provided at the next stage of the inversion circuit 18; 21 is a setting device for setting a reference value (threshold level) by the comparison circuit 20; the detection signal inputted from the comparison circuit 20 is set to the reference value; is compared based on the peak detection signal and output as a peak detection signal. 22 is a timer that receives the peak detection signal from the comparison circuit 20 and outputs a pulse stop signal after a predetermined time (for example, 0.5 seconds);
A CR timer is used, and its delay time depends on the diameter of the container body 1 and the stepping motor 1.
The step angle of 1 and the mounting position of the photoelectric sensor 16 are set according to various conditions.

Further, 23 is a motor drive circuit provided at the next stage of the timer 22 to control the output and stop of the output of pulse signals to the stepping motor 11, and 24 is a motor drive circuit that generates a pulse signal for driving the stepping motor consisting of a clock pulse. The pulse generator 25 is a position detection sensor that detects that the holder 15 carrying the container body 1 carried by the carrying means has arrived at a predetermined position and outputs a motor start signal, and is connected to the motor drive circuit. 23 is position detection sensor 2
A function to output a pulse signal from the pulse generation circuit 24 to the stepping motor 11 when a motor start signal is input from the timer 5, and to stop outputting the pulse signal to the stepping motor 11 when a motor stop signal is input from the timer 22. has.

In the mark detection device for a detected object configured as described above, when the position detection sensor 25 detects the arrival of the holder 15, it outputs a motor start signal to the motor drive circuit 23, and the motor drive circuit 23 is connected to the pulse generator 24. A pulse signal is applied to the stepping motor 11 to rotate it at a predetermined step angle. Then, the stepping motor 11 rotates the rotating shaft 13 and the holder attachment/detachment device 14 via the belt 12. In this state, when the holder 15 reaches the position of the holder attachment/detachment device 14, the holder 1
5 is magnetically attached to this and rotates integrally with it, and the container body 1 also rotates together with this.

However, when the photoelectric sensor 16 detects the matching mark 3 on the container body 1, the photoelectric sensor 16 outputs a detection signal shown in FIG. On this occasion,
If the peak value falls due to the relationship between the ground color of the container body 1 and the match mark 3 (as in the case of FIG. 5), an inversion signal is input to the inversion circuit 18 by the ground color changeover switch 19. As a result, the inversion circuit 18 inverts the peak value of the input detection signal, and the comparison circuit 18 inverts the peak value of the input detection signal.
Output to 0. It should be noted that when the peak value rises (as in the case of FIG. 6), the ground color changeover switch 19 is not switched, and therefore the inversion circuit 18 is not activated.

On the other hand, the comparison circuit 20 compares the peak value of the detection signal inputted from the inversion circuit 18 with the reference value set in the setting device 21, and outputs a peak detection signal to the timer 22 if the peak value is equal to or higher than a predetermined level. . As a result, the timer 22 outputs a motor stop signal to the motor drive circuit 23 after a predetermined delay time, and the motor drive circuit 23 stops outputting pulse signals to the stepping motor 11.

In this way, the container body 1 is stopped at a predetermined position together with the holder 15, and the holder 15 is detached from the holder attachment/detachment device 14 and conveyed again to the next process by the conveying means, where it is filled with cosmetics and the like, and the container body is removed. 1 is crimped at the bottom.

[Problems with conventional technology]

However, the prior art described above has the following problems. That is, first, the container body 1
Based on the relationship between the background color and the matching mark 3, if the background color is white (bright) and the matching mark 3 is black (dark), the peak value will be inverted. An inverted signal must be output to 18. As a result, there is a drawback that it is necessary to operate the background color changeover switch 19 each time the background color is changed.

Second, since the comparator circuit 20 sets the reference value using the setting device 21, it is necessary to fine-tune the threshold level every time the color difference between the ground color and the match mark 3 differs. There are drawbacks,
Especially when the color difference is small, skill is required.

Thirdly, since the comparison circuit 20 compares the first peak value inputted from the inversion circuit 18 with the reference value, it is possible to avoid variations in each item of the container body 1, especially due to scratches, dirt, deformation, etc. There is a drawback that the peak value may be judged as match mark 3, and it cannot be adequately handled.

Fourth, since the timing of the motor stop signal is based on time management by the timer 22,
When a CR timer is used, it is susceptible to disturbances such as temperature and resistance, and has the disadvantage of poor positioning accuracy.

The present invention was developed in view of the problems of the prior art described above, and even if the color difference varies from product to product, the peak value can be held by pressing the test switch once, and the reference value ( The stepping motor can be rotated twice, the first peak value is compared with the reference value and stored, and the second peak value is compared with the reference value. By determining the point of output as the position of the match mark, it is possible to stably detect scratches, dirt, deformation, eccentricity, etc. on each product.Furthermore, the stopping timing of the stepping motor is determined by counting pulse signals. That is, 0.9° to 1.8° (1
It is an object of the present invention to provide a mark detection device for a detected object without adjustment, which is capable of stopping at a step angle of .about.2 pulses.

[Means for solving problems]

In order to solve the above problems, the present invention includes a motor control circuit that rotates a stepping motor based on a pulse signal, a photoelectric sensor that detects a mark on an object rotated by the stepping motor, and a photoelectric sensor that detects a mark on an object rotated by the stepping motor. A negative component inversion circuit that inverts only the negative component of the signal detected by the photoelectric sensor, a peak hold circuit that stores the signal output from the negative component inversion circuit, and each signal from the negative component inversion circuit and the peak hold circuit. a comparison circuit that compares the signals and outputs a signal when the signal is equal to or higher than a reference value; a peak counter that counts the signals from the comparison circuit and outputs a peak detection signal when a predetermined number is reached; and a pulse counter that counts pulse signals from the motor control circuit based on the pulse signal and outputs a motor stop signal to the motor control circuit when a predetermined number is reached.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail based on FIGS. 1 and 2. Note that the same components as those in the prior art described above are given the same reference numerals, and the explanation thereof will be omitted.

In the figure, numeral 31 is a photoelectric sensor for detecting the matching mark 3. As the photoelectric sensor 31, a phototransistor, a photodiode, etc. can be used as in the conventional technology, or a solar cell analog sensor etc. can be used. , outputs a detection signal similar to that shown in FIG. Note that when a phototransistor or the like is used as the photoelectric sensor 31, the output voltage reaches a saturation voltage above a predetermined voltage level, but when a solar cell analog sensor is used, the increase and decrease of reflected light is linear. , the detection accuracy can be further improved.

32 is an amplifier circuit for amplifying the detection signal of the photoelectric sensor 31; 33 is a negative component inversion circuit provided at the next stage of the amplifier circuit 32;
Unlike the inversion circuit 18 of the prior art, which operates in response to a command from the background color changeover switch 19,
It is configured to automatically invert only the negative component of the biased AC waveform. The negative component inverting circuit 33 has a structure in which, for example, dual differential amplifiers are provided to allow positive signals to pass through and invert only negative signals.

34 is a peak hold circuit that holds the peak value voltage of the detection signal after negative component inversion inputted from the negative component inversion circuit 33, and the BUSY signal is inputted to the peak hold circuit 34 from a switching circuit 46 to be described later. The hold state of the peak value voltage is updated only during this period, and when the BUSY signal is not input, the hold state is maintained and the peak value voltage is stored.

35 is a comparison circuit provided at the next stage of the peak hold circuit 34, and the comparison circuit 35 uses the voltage value of the peak value voltage from the peak hold circuit 34 as a reference to invert the negative component input via the signal line 36. The voltage value of the detection signal from the circuit 33 is compared, and if the voltage value is equal to or higher than a reference value (for example, a voltage value of 80% of the peak value voltage), a pulse signal is output.

37 is a peak counter that counts the pulse signal output from the comparison circuit 35 and outputs a peak detection signal when a predetermined pulse is reached. As the peak counter 37, for example, a preset counter is used, and as will be described later, the peak counter 37 outputs a peak detection signal. Ping motor 11
In order to output a peak detection signal when rotates twice,
Usually 4 pulses are preset.

38 is a pulse counter provided at the next stage of the peak counter 37, and 39 is a stepping motor 11.
40 is a motor control circuit consisting of a pulse generator 41 and a motor drive circuit 42.

Here, the pulse counter 38 is, for example, a preset counter, and the piece counter 37
When a peak detection signal is input from the traffic light 43
The digital switch 39 starts counting pulse signals input from the pulse generator 41 via the digital switch 39.
It has a function of outputting a motor stop signal to the pulse generator 41 via the signal line 44 when the set number of pulses is reached. On the other hand, similarly to the timer 22 according to the prior art, the stop position setting digital switch 39 adjusts the stepping motor 11 according to the diameter of the container body 1, the step angle of the stepping motor 11, the mounting position of the photoelectric sensor 31, etc. In this embodiment, the timer 2 is used to set the stop position of the timer 2.
This differs from No. 2 in that the stopping accuracy is increased by setting the number of pulses (step angle).

Further, the motor control circuit 40 starts generating a pulse signal for driving the stepping motor consisting of a clock pulse based on a motor start signal inputted from a switching circuit 46 (to be described later) via a signal line 45. a pulse generator 41 that stops generating pulse signals based on a motor stop signal from the pulse counter 38 via the pulse generator 41;
The stepping motor 1 is activated by the pulse signal from
1 and a motor drive circuit 42 that drives the motor. Note that the pulse generator 41 is connected to signal lines 44 and 45.
The signal lines 44 and 45 can be eliminated and the signal lines 44',
45' may be connected to the motor drive circuit 42.
In this case, the pulse generator 41 only has the function of constantly generating clock pulses, and the motor drive circuit 42 opens the gate of the pulse signal to the stepping motor 11 based on the motor start signal from the signal line 45'. , the gate is closed based on the motor stop signal from the signal line 44', and the configuration is similar to that of the motor drive circuit 23 in the prior art.

Further, reference numeral 46 denotes a switching circuit constituted by, for example, a C-MOS semiconductor element, and 47 denotes a holder 15 on which the container main body 1 carried by a conveying means is placed in a predetermined position, similar to the position detection sensor 25 according to the prior art. A position detection sensor 48 for detecting the arrival at the position is operated every time the type of container body 1 conveyed by the conveyance means changes, and operates a test switch for storing the peak value voltage in the peak hold circuit 34. Each is shown below. Here, the input side of the switching circuit 46 is connected to a position detection sensor 47 and a test switch 48, and the output side is connected to the pulse generator 41 via a signal line 45 (or to the motor drive circuit 42 via a signal line 45'). The BUSY terminal is connected to the peak hold circuit 34.
is connected to. The switching circuit 46 normally outputs a motor start signal to the signal line 45 when the position detection sensor 47 is differentially actuated, and outputs the motor start signal to the signal line 45 when the test switch 48 is pressed.
It has the function of outputting a BUSY signal to update the peak value voltage.

The present embodiment is constructed as described above, and its operation will now be described with reference to FIG. 2.

First, it is assumed that the peak hold circuit 34 stores the peak value voltages related to the match marks 3 attached to a series of container bodies 1 transported by the transport means (see FIG. 2C).

Now, when the position detection sensor 47 detects the arrival of the holder 15, the sensor 47 outputs a detection signal shown in FIG. As a result, the switching circuit 46 outputs a motor start signal to the pulse generator 41 from the signal line 45, and causes the pulse generator 41 to generate a pulse signal. As a result, the pulse signal from the pulse generator 41 is applied to the stepping motor 11 from the motor drive circuit 42,
The stepping motor 11 is rotated at a predetermined step angle (see FIG. 2). In this state, when the holder 15 reaches the position of the holder attachment/detachment device 14, the holder 15 is magnetically attached to it and rotates together with it, and the container body 1 also rotates together with it.

However, when the photoelectric sensor 31 detects the match mark 3 on the container body 1, the detection signal from the photoelectric sensor 31, for example, the detection signal shown in FIG. , only the negative component of the detected signal is inverted and converted into a signal waveform like the twin peaks shown in FIG. 2(b). Next, the signal from the negative component inversion circuit 33 is transmitted to the signal line 36.
is input to the comparator circuit 35 via the comparator circuit 3
5 compares the reference value based on the peak value voltage stored in the peak hold circuit 34 (for example, see the dotted lines shown in FIG. 2 C and B) with the signal from the negative component inversion circuit 33, If so, the pulse signal shown in FIG.
Output.

Here, since 4 pulses are set in advance as a preset value in the peak counter 37,
Two pulses are counted for each rotation of the stepping motor 11, and when a total of four pulses is reached, a peak detection signal shown in FIG. Here, the reason why 4 pulses are preset in the peak counter 37 is as follows: First, when the stepping motor 11 is rotating at the rated condition, the timing mark 3
Second, during the first rotation of the stepping motor 11, the detection signal is compared with the reference value to determine the match mark 3, and
This is to determine the position of match mark 3 when the same detection signal is obtained again in the second rotation.
Thirdly, due to the second reason, scratches, dirt, deformation, etc.
This is to prevent false detection due to eccentricity or the like.

When the peak detection signal is input to the pulse counter 38 as described above, the counter 38 opens the gate for the pulse signal from the pulse generator 41 input via the signal line 43, and Start counting. Then, the stop position setting digital switch 39 sets a predetermined value (for example, if one rotation of the stepping motor 11 is 400 steps and the motor is stopped at 9 degrees after detection of match mark 3, 10 pulses are set). ), the signal line 44 is connected from the pulse counter 38 to the pulse generator 41.
A motor stop signal is output via the motor (see Fig. 2). As a result, the generation of pulse signals from the pulse generator 41 is stopped, and the output from the motor drive circuit 42 to the stepping motor 11 is also stopped (second
(see Figure H), the step pig motor 11 stops.

Thus, the container body 1 together with the holder 15 is stopped at a predetermined position, and the holder 15 is detached from the holder attachment/detachment device 14 and conveyed again to the next process by the conveyance means.

Furthermore, when the container body 1 changes and the color difference between it and the matching mark 3 changes, the test switch 4
Press 8. As a result, a BUSY signal is output from the switching circuit 46 to the peak hall circuit 34,
The peak value voltage in the peak hold circuit 34 is reset, and the highest voltage among the detection signals inputted from the negative component inverting circuit 33 is updated and stored as the peak value voltage. Therefore, in this embodiment, the comparison circuit 35 can automatically determine the reference value based on the peak value voltage in the peak hold circuit 34.

The embodiments of the present invention are as described above, and in the embodiments, the container body 1 was taken as an example of the object to be detected.
The present invention is not limited to this, but can be widely applied to rotating bodies, and can also be applied, for example, to mark detection devices such as automatic labeling devices, automatic container printers, automatic machine tools, and industrial robots. Further, although it has been described that the peak value of the detection signal is stored in the peak hold circuit 34 as a peak value voltage, a reference value may be stored in the peak hold circuit 34. Furthermore, peak counter 3
7 is described as setting 4 pulses, but
It is also possible to set 6 pulses or more (when the stepping motor 11 rotates 3 times).

〔Effect of the invention〕

Since the mark-adjustment-free detection device for the object to be detected according to the present invention is as described in detail above, the reference value can be automatically set by the comparison circuit regardless of the color difference between the ground color and the mark, and the reference value can be automatically set by the comparison circuit. By rotating the detection object twice or more, stable and highly accurate mark detection can be performed, and since the stopping position of the stepping motor is determined by pulse calculation, the positioning accuracy when stopped is improved. It has the following effects:

[Brief explanation of drawings]

FIGS. 1 and 2 relate to embodiments of the present invention,
Figure 1 is a circuit configuration diagram, Figures 1 to 2 are waveform diagrams of each signal, and Figures 3 to 7 are related to the prior art.
Fig. 3 is a perspective view showing the tube container before crimping, Fig. 4 is a perspective view showing the tube container after crimping, and Fig. 5 is a perspective view showing the tube container before crimping.
The figure is a waveform diagram showing the detection signal of a matching mark when the background color is white, Figure 6 is a waveform diagram showing the detection signal of a matching mark when the background color is black, and Figure 7 is a conventional technique. The circuit configuration diagram is shown below. 1... Container body, 3... Matching mark, 11... Stepping motor, 31... Photoelectric sensor, 33...
... Negative component inversion circuit, 34 ... Peak hold circuit, 37 ... Peak counter, 38 ... Pulse counter, 39 ... Digital switch for setting stop position, 40 ... Motor control circuit, 41 ... Pulse generator, 42 ...Motor drive circuit, 46...Switching circuit, 47...Position detection sensor, 48...Test switch.

Claims (1)

[Scope of Claims] 1. A motor control circuit that rotates a stepping motor based on a pulse signal, a photoelectric sensor that detects a mark on a detected object rotated by the stepping motor, and detection by the photoelectric sensor. A negative component inversion circuit that inverts only the negative component of the signal, a peak hold circuit that stores the signal output from the negative component inversion circuit, and each signal from the negative component inversion circuit and the peak hold circuit is compared. , a comparison circuit that outputs a signal when the signal is equal to or greater than a reference value; a peak counter that counts the signals from the comparison circuit and outputs a peak detection signal when the signal reaches a predetermined value; A non-adjustable mark detection device for a detected object, comprising a pulse counter that counts pulse signals from a motor control circuit and outputs a motor stop signal to the motor control circuit when a predetermined number is reached. 2. The non-adjustable mark detection device for a detected object according to claim 1, wherein the peak hold circuit stores the peak value only when a test switch is activated. 3. The non-adjustable mark detection device for a detected object according to claim 1, wherein the peak counter outputs a peak detection signal when four pulses of the pulse signal are input from the comparison circuit.