JPH0979823A - Object measuring method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect an end part of an object even if a length of a heterogeneous material changes by projecting plural light emitting wave lengths in order on the object, and measuring a length of the heterogeneous material according to a difference in transmissivity between the heterogeneous material and the object in the respective light emitting wave lengths. SOLUTION: An fluff part (a heterogeneous material) of sample cloth or cloth to be sewn (an object) is set in a transmissivity measuring solar cell 4a, and transistors Q1 to Q4 are driven in order by a light emitting wave length selecting command of a microcomputer 17, and when respective diodes R, G, B and IR of a surface emmisive LED panel 3 are made to emit the light in order, the light passing through the fluff part or the cloth irradiates the cell 4a, and voltage according to a quantity of light is outputted from a light detecting circuit 12a. Next, voltage corresponding to the disturbance light is removed (13a) from this voltage, and is inputted to the microcomputer 17 through an A/D converter 16 after it is held (14a), and is compared with a quantity of received light of the cell 4a at fully opened time, and transmissivity of fluff or the cloth in respective light emitting wave lengths is found, and a length of the cloth and the fluff is calculated by these transmissivity and received light voltage of the cloth end position measuring solar cell 4a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring an object, and more particularly, to a method for measuring an object which has a heterogeneous portion with different transmittance at the edge and which changes in accordance with a change in the edge position of the object. The present invention relates to an object measuring device that measures the edge position of an object by measuring the amount of received light.

[0002]

2. Description of the Related Art Conventionally, in the sewing field of sewing machines, for example, two fabrics having different cloth end curves have been automatically sewn while aligning the cloth ends (for example, Japanese Patent Publication No. (See JP-A-3-44548). In such a sewing machine, a thin plate-shaped LED panel provided with a plurality of LED (light emitting diode) elements and a solar cell are arranged so as to be opposed to each other with respect to each of two sewn objects. , Turn on and off the LED element,
The amount of ambient light received when the LED is turned off is removed from the amount of light received by the solar cell, and the edge position of the cloth is detected based on the amount of light of the LED element.

[0003]

However, in a conventional cloth edge position measuring device using a combination of a thin plate-shaped LED panel and a solar cell, the amount of light received by the solar cell is related to the transmittance of the cloth. If there is a fluff, the transmittance of the fluff portion is different from the transmittance of the cloth, and if the length of the fluff is not constant, an error may occur in the measured value of the cloth edge position, which is a problem. is there.

The above has been the problem of detecting the edge position of cloth in the sewing field of sewing machines.
There is a similar problem with sheet-like objects such as paper. For example, when detecting the edge of a sheet of a patterned film or paper, the same problem occurs when there is a colored portion at the edge and the width is not constant.

Therefore, the present invention has been made in view of the above problems, and the end portion of the object to be measured has a color pattern or a foreign portion having different transmission characteristics. An object of the present invention is to provide a method and apparatus for measuring an object that can accurately measure the position.

[0006]

The amount of light received from an object is related to the transmittance of the object for which the amount of received light is measured. There is a foreign part with different transmittance at the edge position of the object,
If the widths of the different portions are different, the amount of light received from the object becomes a function of the end position and the width of the different portion, so that an error occurs in the measurement of the end position. Therefore, in the present invention, the width (length) of this foreign portion is measured.

Therefore, in the present invention, a plurality of emission wavelengths are sequentially switched and projected onto the object, and the transmittances of the foreign portion and the object are measured for each emission wavelength. An emission wavelength suitable for receiving the object is selected from the transmittance of the object, and the respective transmittances of the heterogeneous part and the object at the emission wavelength other than the selected emission wavelength and visible light, the selected emission wavelength and the visible light The length of the foreign portion is measured based on the amount of each received light from the object including the foreign portion having an emission wavelength other than light.

As described above, according to the present invention, the length of the foreign portion can be measured by utilizing the difference between the transmittances of the foreign portion and the object at each emission wavelength of visible light and other than visible light, such as infrared light. Therefore, even if the length of the foreign portion changes, the end position of the object can be accurately detected.

In a preferred embodiment of the present invention, the transmissivity of the foreign portion and the object is based on the ratio of the received light amount for each emission wavelength to the received light amount for each emission wavelength when there is no foreign portion or object. Is required.

The present invention is particularly advantageous when measuring the end position of the sewing cloth. For example, when cutting a cloth,
Since the fluff portion is generated and this fluff portion is different from the transmittance of the cloth, if the width (length) of the fluff portion is different, an error occurs in the end position of the cloth. However, in the present invention, since the positions of the fluff portion and the end portion of the cloth can be detected, even if there is the fluff portion, it is possible to sew with an accurate seam allowance.

In a preferred embodiment, the light receiving means comprises a first light receiver for receiving light from the object or a foreign part to determine the transmittance, and an object or object to measure the edge position of the object. A second light receiver for receiving light from the foreign portion.

The light emitting means may be composed of a single light emitting device, or a first light emitting device for projecting light of a plurality of emission wavelengths on the object for measuring the transmittance and an end of the object. It may be configured with a second light emitter that projects light of a plurality of emission wavelengths onto an object for measuring the position of a part.

The light emitting means is composed of, for example, a light emitting diode which emits light of different emission wavelengths, and a driving means which sequentially pulse-drives these light emitting diodes. In that case,
The light emitting diode is arranged so that an object can be uniformly illuminated for each light of each emission wavelength. The light emitting diode is, specifically, a chip element, a rod-shaped array in which the chip elements are arranged in a rod shape, or a wide directional diode.

At the time of measuring the transmittance or the edge position, the disturbance light signal is removed or measured from the signal corresponding to the amount of light received from the object or the foreign part irradiated by the pulse-driven light emitting diode. The temperature correction or the light amount correction is performed on the signal corresponding to the received light amount from the object or the foreign portion.

The transmittance measuring means and the end position measuring means may each have a detection circuit for detecting the amount of received light, or these detection circuits may be shared.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. In the example shown below, the description will be given based on an example of measuring the end position of the sewing cloth of the sewing machine, but the present invention is not limited to such a sewing cloth, and a sheet-shaped product such as a film or paper. It is also applied to the case of detecting the end position.

FIG. 1 schematically shows a sewing machine equipped with an edge position measuring device having an emission wavelength automatic switching function, which is an embodiment of the present invention. In the figure, reference numeral 1 indicates a sewing machine head, 2 indicates a sewing needle, and in the vicinity of the needle drop point of the needle 2, light emitting means of surface emitting LED (light emitting diode) panels 3 and 3 ', for example, The light receiving means of the single crystal type solar cells (photodiodes) 4 and 4'are arranged to face each other so as to overlap in the vertical direction.

The surface emitting LED panels 3 and 3'and the solar cells 4 and 4'are provided for the upper cloth and the lower cloth via the separating plate 5, and both of them are in a stacked state. This device
Applicable to a sewing machine that inserts an upper cloth with different cloth edge curves between the LED panel 3 and the solar cell 4 and a lower cloth between the LED panel 3'and the solar cell 4'and automatically sews while aligning the respective cloth edges. Has been done.

The surface emitting LED panels 3 and 3'and the solar cells 4 and 4'have the same structure. In FIG. 2, the surface emitting LED panel 3 for the upper cloth, the solar cells 4, the separating plate 5 and the upper cloth. 7 is shown and the solar cell 4
Is composed of a solar cell 4a for measuring the transmittance and a solar cell 4b for measuring the cloth edge position.

As shown in FIG. 3, the surface-emitting LED panel 3 includes an LED element chip 3a and LEs thereof.
Panel printed circuit board 3b on which D element chip 3a is arranged
And a case 3d that surrounds the LED element chip 3a and a semi-transparent film 3c for light diffusion that covers the opposite side of the case 3d from the printed circuit board. When the LED element chip 3a emits light, the diffusion film 3c is formed. It is configured so that a uniform amount of light can be obtained from the surface of the.

Further, in this example, the LED element chip 3a includes red (R), green (G), blue (B), infrared (I).
As shown in R), the circuit is configured such that LEDs having different wavelengths are regularly arranged and only the LEDs having the same wavelength can be independently turned on. The LEDs are arranged in such an arrangement that a uniform amount of light can be obtained on the surface of the diffusion film 3c when the LEDs are individually turned on for each wavelength. As an example, as shown in the drawing, the matrix is arranged in the vertical and horizontal directions, but it may be a hexagonal lattice-shaped point or the like, and many other arrangement patterns are conceivable.

As shown in FIG. 2, at the time of sewing, an upper cloth 7 is provided between the surface emitting LED panel 3 and the solar cell 4 and, although not shown, between the surface emitting LED panel 3'and the solar cell 4 '. Allows the lower cloths to pass therethrough at a fixed distance from each other, and the end position of each cloth end is measured as described below. When the positions of the respective cloth ends are displaced, the sewing is performed while correcting the position of the displaced fabric, and the sewing is automatically performed while aligning the respective fabric ends.

FIG. 4 shows a circuit configuration of an edge position measuring device including the light emitting LED panel 3 and the solar cells 4a and 4b whose light emission colors can be switched.

In FIG. 4, reference numeral 10 indicates an oscillator as a pulse generating means, and the pulse from the oscillator 10 is
It is input to one terminal of the gates U1 to U4 of the LED drive circuit 11, and the other terminal of these gates is connected to the emission wavelength selection line from the microcomputer 17. The outputs of the respective gates U1 to U4 are resistors R1 to R4.
Is connected to the bases of the transistors Q1 to Q4 via.

The surface emitting LED panel 3 is connected to the LED drive circuit 11 and each diode (R), (G), (B), corresponding to red, green, blue and infrared of the LED panel 3 is connected.
(IR) is connected to the collectors of the transistors Q1 to Q4 via resistors R5 to R8, respectively. Therefore, when the red, green, blue, and infrared selection lines are selected from the microcomputer 17, the transistors Q1 to Q4 are driven in synchronization with the pulse from the oscillator 10, and the diodes of the LED panel 3 are driven. Is driven.

The transmittance measuring light amount detection circuit 12a comprises a solar cell 4a, an operational amplifier U5, a resistor R9 and a capacitor C1. The output of the detection circuit 12a is a transistor Q5, an inverter U6, a capacitor C2 and resistors R10, R11 and R12. Is input to the pulse amount detecting circuit 13a as a noise removing unit. The pulse from the oscillator 10 is input to the inverter U6 of the pulse amount detection circuit 13a. Sample and hold circuit 14a
Is connected to the pulse amount detection circuit 13a and samples and holds the pulse of the pulse amount detection circuit 13a according to the pulse from the oscillator 10.

The light amount detecting circuit 1 is also used for measuring the cloth edge position.
2b, a pulse amount detection circuit 13b and a sample & hold circuit 14b are provided, and the light amount detection circuit 12b is provided.
Is a solar cell 4b, an operational amplifier U7 and a resistor R1.
3 and a capacitor C3, and the pulse amount detection circuit 13b includes a transistor Q6, an inverter U8, a capacitor C4 and resistors R14, R15 and R16. The sample & hold circuit 14b responds to a pulse from the oscillator 10. Then, the pulse of the pulse amount detection circuit 13b is sampled and held.

The analog multiplexer 15 selects the signals of the sample & hold circuits 14a and 14b according to the switching signal of the microcomputer 17, and inputs them to the microcomputer 17 via the A / D converter 16. In addition, the circuit of FIG. 4 is provided with a one-shot circuit 18, which detects a pulse having a predetermined pulse width T1 from the pulse from the oscillator 10.
Pulse is formed and a read timing pulse is supplied to the microcomputer 17.

When a cloth portion to be sewn has a fluff portion which is a foreign portion, the fluff portion has a transmittance different from that of the cloth portion, so that the circuit of FIG. A fluff transmittance measuring switch 50 for measuring the rate is provided, and the switch operation signal is supplied to the microcomputer 17
It is connected to the.

The circuit described above is for the upper cloth, but a similar circuit configuration is provided for the lower cloth, but the illustration is omitted.

Next, the circuit operation of the edge position measuring device having the automatic emission wavelength switching function will be described below.

First, in order to obtain the transmittance of the fluff portion prior to the processing, the fluff portion of the sample cloth is set in the solar cell 4a for transmittance measurement, and then the flicker transmittance measurement switch 50 is operated.

If it is determined in step S1 of FIG. 5 that the flash transmittance measuring switch 50 has been operated, then in step S2 of FIG. 5, the R (red) LED is output from the emission wavelength selection output of the microcomputer 17. The selection is output (FIG. 8 (d)). Therefore, the gate U1 of the LED drive circuit 11 is opened, and as shown in FIG. 8 (h), the red LED portion is driven in synchronization with the pulse from the oscillator (FIG. 8 (c)), and the surface emitting LED is driven. The panel 3 emits a pulsed light in red.

When the surface emitting LED panel emits a pulsed light in red, the fluffed portion of the sample cloth is uniformly illuminated. Therefore, the transmittance measuring solar cell 4a is irradiated with the amount of light transmitted through the fluff portion.

When the transmittance measuring solar cell 4a is irradiated, a photocurrent is generated in proportion to the amount of light, but the resistance R9
Since the same amount of current as the photocurrent flows to cancel the photocurrent, the voltage between the positive and negative inputs of the operational amplifier U5 is maintained at 0 volt. Therefore, the output voltage of the operational amplifier U5 becomes a value obtained by multiplying the photocurrent of the solar cell by the resistance value of the resistor R9, and the light amount detection circuit 12a produces an output as shown in FIG.

In FIG. 8 (l), the LED element 3
The part A protruding upward when the switch is on is the LED element 3
The voltage corresponding to only the light amount of a, and the diagonal line B when the LED element 3a is off indicate the voltage corresponding to the amount of ambient light such as an incandescent lamp or a fluorescent lamp or the ambient light such as sunlight.

In the pulse amount detecting circuit 13a constituted by the differentiating circuit, when the LED element 3a is off, the transistor Q5 is conductive, so that the output is 0 volt. At this time, the transistor Q5 conducts in both the normal direction and the reverse direction. Here, the LED element 3a
Assuming that the output voltage of the light amount detection circuit 12a immediately before turning on is, for example, 4 volts, the transistor Q5 is on, so the capacitor C2 has a charge of 4 volts.
Here, when the LED element 3a turns on, the transistor Q5 turns off at the same time, and the output voltage of the light amount detection circuit 12a changes to
For example, if the voltage is changed to 7 V, the capacitor C2 has a charge of 4 V as described above, so that the pulse detection circuit 13a outputs a pulse voltage of (7-4) = 3 V. Will be done. However, R10 << R
It is assumed to be 12.

Incidentally, since the transistor Q5 is off while the LED element 3a is on, the voltage of the pulse detection circuit 13a decreases due to the time constant of C2 × R12, but C2 × R.
12 >> (pulse width when the LED element 3a is on), the pulse voltage value can be regarded as constant while the LED element 3a is on. Then, when the LED element 3a is turned off again,
Transistor Q5 conducts and its output goes to 0 volts.

If there is no transistor Q5, the time constant of C2 × R12 is considerably large, and therefore L
The response of the terminal voltage of the capacitor C2 is delayed with respect to the voltage due to only the ambient light when the ED element 3a is off, and the pulse output voltage becomes unstable.

In this way, the pulse component detection circuit 13a
The voltage output from is shown in FIG. 8 (n). As shown in the figure, the voltage B corresponding to the light quantity of the disturbance light described in FIG.
Therefore, only the voltage A corresponding to only the light amount of is output.

The output of the pulse amount detection circuit 13a is input to the sample & hold circuit 14a. In the sample & hold circuit 14a, the voltage A corresponding to only the light quantity of the LED element 3a is output at the timing when the LED element 3a is turned on. To be held. This waveform is shown in FIG. 8 (p).

The output of the sample-and-hold circuit 14a is input to the analog multiplexer 15, and in the analog multiplexer 15, the sample-and-hold circuit 14a is selected by the switching signal output from the microcomputer 17, and the A / D. It is input to the converter 16.

The output of the A / D converter 16 is input to the microcomputer 17. At this time, the one-shot multivibrator 18 that outputs a pulse having a width of time T1 in synchronization with the pulse output of the oscillator 10 which is the timing of turning on the LED element 3a reads the light amount as shown in FIG. A timing signal is generated (step S3 in FIG. 5), and the A / D is activated by turning on the LED element 3a
After a time T1 that is longer than the time required for the light quantity to be converted into digital data by the converter 16, the microcomputer 17
The received light voltage VR 'due to the R (red) LED light emission is read in and stored in the register (step S4 in FIG. 5).

In the next step S5, the amount of received light VR 'for the emission wavelength of red thus obtained and the amount of received light VR0 of the sensor for measuring the transmittance when the solar cell 4a is fully opened are stored in advance in the microcomputer. The transmittance VR '/ VR0 of the fluff part for the red emission wavelength is obtained,
Stored in memory.

Next, in step S6, R (red) L
The selective output of the ED is turned off, and in step S7,
The emission wavelength selection output of the microcomputer 17 is G
(Green) Switch to LED selection. This switching state is illustrated in FIGS. 8D and 8E. At this time,
The gate U1 of the LED drive circuit 11 is closed and the gate U2 is opened instead, and the portion of the G (green) LED is driven in synchronization with the next pulse output of the oscillator 10 (see FIG. 8).
(I)), the surface-emitting LED panel 3 emits pulsed green light.

Then, the microcomputer 17 performs G (green) by the same processing as when the R (red) LED emits a pulse.
The received light voltage VG ′ due to the LED light emission is read, is held in the register, and is divided by the received light amount VG0 of the sensor for measuring the transmittance when the solar cell 4a is fully opened, which is previously stored in the microcomputer, and is divided by the green light emission wavelength. The transmittance of the fluffy portion is obtained and stored in the memory (steps S8, S9, S10).

Next, as shown in steps S11 and S12, the emission wavelength selection output of the microcomputer 17 is switched to B (blue) LED selection (see FIGS. 8 (e) and 8 (f)). , The gate U of the LED drive circuit 11
2 is closed and the gate U3 is opened instead, and in synchronization with the next pulse output of the oscillator 10, the portion of the B (blue) LED is driven (FIG. 8 (j)), and the surface emitting LED panel 3 turns blue. It emits pulsed light.

Then, R (red) LED and G (green) L
By the same processing as that of the ED pulse emission, the transmittance for the emission wavelength of blue is determined by the value of the reception voltage VB 'by the B (blue) LED emission in the microcomputer 17 and the reception voltage VB0 stored in advance when the solar cell 4a is fully opened. Is calculated and stored in the memory (steps S13, S14, S1
5) In step S16, the selection output of the B (blue) LED is turned off.

Next, as shown in step S17 of FIG. 6, the emission wavelength selection output of the microcomputer 17 is
Switch to IR (infrared) LED selection (Fig. 8 (f),
(G)). The gate U3 of the LED drive circuit 11 is closed and the gate U4 is opened instead, and the portion of the IR (infrared) LED is driven in synchronization with the next pulse output of the oscillator 10 (FIG. 8 (k)), and the surface emission is performed. The LED panel 3 emits infrared pulsed light.

Then, R (red) LED and G (green) L
IR (infrared) LED is applied to the microcomputer 17 by the same process as the pulse emission of ED and B (blue) LED.
The transmittance for the infrared emission wavelength is calculated from the value of the received light voltage VIR ′ due to the light emission and the previously stored value of the received light voltage VIR0 when the solar cell 4a is fully opened and stored in the memory (steps S18, S19, S20), and step S21.
At, the selective output of the IR (infrared) LED is turned off.

By the processing described above, the transmittances VR '/ VR0, VG' / VG0, VB '/ VB0 of the fluff portion at the respective emission wavelengths,
VIR '/ VIR0 is calculated.

Next, cloth is set to start sewing, and the start switch is turned on as shown in step S22 of FIG. This state is shown in FIG. 8B, whereby the R (red) LED is selectively output in the emission wavelength selection output of the microcomputer 17 (step S23, FIG. 8D). Therefore, the gate U1 of the LED drive circuit 11 is opened, and as shown in FIG.
The red LED portion is driven in synchronization with the pulse from the oscillator, and the surface emitting LED panel 3 emits red pulse light.

When the surface emitting LED panel emits a pulsed light in red, as shown in FIG. 2, the cloth edge position measuring solar cell 4b and the cloth 7 during the feeding operation are uniformly irradiated. Therefore, in the cloth edge position measuring solar cell 4b, the light amount that is not shielded by the cloth 7 is emitted as it is, and the light shield portion is irradiated with the light amount that has passed through the cloth 7.

In steps S24 and S25, the light reception voltage VR by the R (red) LED emitted from the solar cell 4a for transmittance measurement is held in the register read by the microcomputer in the same manner as in the above-described flicker transmittance measurement. FIG. 8 (p)).

Similarly, the solar cell 4 for measuring the cloth edge position
The light quantity detection circuit 1 for measuring the light quantity applied to b
2b (FIG. 8 (m)), the disturbance light component is removed by the pulse amount detection circuit 13b (FIG. 8 (o)), and held by the sample & hold circuit 14b (FIG. 8).
(Q)). This value is transferred to the microcomputer 17 via the analog multiplexer 15 and the A / D converter 16.
Is read as the received light voltage VRx by the R (red) LED and is held in the register (step S26).

Next, in step S27, the selection output of the R (red) LED is turned off, and in step S28, the emission wavelength selection output of the microcomputer 17 is
Switch to G (green) LED selection. This switching state is illustrated in FIGS. 8D and 8E. At this time, the gate U1 of the LED drive circuit 11 is closed and the gate U2 is opened instead, and the portion of the G (green) LED is driven in synchronization with the next pulse output of the oscillator 10 (see FIG. 8).
(I)), the surface-emitting LED panel 3 emits pulsed green light.

Then, the microcomputer 17 performs the same processing as that for the pulse emission of the R (red) LED.
Light receiving voltages VG and VGx by G (green) LED emission as shown in (p) and (q) are read and held in the register (steps S29, S30, S31).

Next, in step S32, LE for G (green)
The selection output of D is turned off, and in step S33 of FIG. 7, the emission wavelength selection output of the microcomputer 17 is switched to B (blue) LED selection ((FIG. 8 (e),
See FIG. 8 (f). As a result, the LED drive circuit 1
The gate U2 of 1 is closed, the gate U3 is opened instead, and the B (blue) LED is synchronized with the next pulse output of the oscillator 10.
Is driven (FIG. 8 (j)), and the surface emitting LED panel 3 emits blue pulse light.

Then, R (red) LED and G (green) L
By the same processing as that of the ED pulse emission, the microcomputer 17 reads the received light voltages VB and VBx by the B (blue) LED emission as shown in FIGS. 8 (p) and (q) and holds them in the register. (Steps S34, S3
5, S36).

Next, in step S37, LE of B (blue) is obtained.
The selective output of D is turned off, and in step S38,
The emission wavelength selection output of the microcomputer 17 is IR
Switch to (infrared) LED selection ((Fig. 8 (f), Fig. 8
(See (g)). As a result, the LED drive circuit 11
Gate U3 is closed and gate U4 is opened instead, and the IR (infrared) LE is synchronized with the next pulse output of the oscillator 10.
Part D is driven (Fig. 8 (k)), surface emitting LED
The panel 3 emits infrared pulsed light.

Then, R (red) LED and G (green) L
8 (p) and (q) are displayed on the microcomputer 17 by the same process as that of the pulse emission of the ED and B (blue) LEDs.
The received light voltages VIR and VIRx by the IR (infrared) LED emission as shown in FIG. 3 are read and held in the register (steps S39, S40, S41). Then, in step S42, the selective output of the IR (infrared) LED is turned off.

In the following steps S43 to S46,
Solar cell 4 for transmittance measurement obtained as described above
The light receiving voltages VR, VG, VB and VIR obtained by individually lighting the surface emitting wavelength LEDs obtained by a and the light receiving voltages VR0, VG0, VB0 and VIR0 stored in the microcomputer 17 in advance without a cloth are shown. It is used to calculate the fabric transmittances αR, αG, αB, αIR for each emission wavelength.

Then, in step S47, the R
Transmittance α at each emission wavelength of (red), G (green), and B (blue)
The minimum values of R, αG, and αB are obtained. For example, if the transmittance at the red emission wavelength is the minimum, step S48 is performed. If the transmittance at the green emission wavelength is the minimum, step S4 is performed.
9 and the minimum transmittance at the blue emission wavelength,
In step S50, the length of the cloth and the length of the fluff are calculated based on the transmittance of the cloth at the emission wavelength of each minimum value and the infrared emission wavelength, the transmittance of the fluff, and the light receiving voltage of the solar cell 4b.

This calculation method is shown in FIG. In the figure, x1 is the detection length of the cloth 7, x2 is the length of the fluff, and x0
Is the length of the solar cell 4b, the solar cell light receiving voltage VRx at the red emission wavelength can be expressed by the following equation.

[0065]

[Equation 1]

In the above equation, αR is the transmittance of the cloth at the red emission wavelength obtained in step S43, VR '/ VR0 is the transmittance of the fluff at the red emission wavelength obtained in step S5, VR1
Is the received light voltage when the solar cell 4b is fully opened at the red light emission wavelength. The first term is the received voltage of the portion corresponding to x1, the second term is the received voltage of the portion corresponding to x2, and the third term is ,
The received light voltage corresponding to the {x0- (x1 + x2)} part,
It can be seen that the total is the received light voltage VRx.

To summarize this,

[0068]

[Equation 2]

Is obtained.

Similarly, for the solar cell light receiving voltage VIRx at the infrared emission wavelength, αIR is the transmittance of the cloth at the infrared emission wavelength obtained in step S46, and VIR '/ VIR0 is the step S20.
Let VIR1 be the transmittance of the fluff at the infrared emission wavelength obtained in step 1 as the received voltage at full open at the infrared emission wavelength of the solar cell 4b,

[0071]

(Equation 3)

When this is sorted out,

[0073]

(Equation 4)

It becomes

Cloth detection length x obtained from equations (1) and (2)
1 and fluff length x2 are

[0076]

(Equation 5)

Is obtained.

The lengths of the green emission wavelength and the infrared emission wavelength obtained in step S49 are also

[0079]

(Equation 6)

Is obtained. Here, αG is the transmittance of the cloth at the green emission wavelength obtained in step S44, VG '/ VG0 is the transmittance of the fluff at the green emission wavelength obtained in step S10, and V
G1 is the received light voltage when the solar cell 4b is fully opened at the green emission wavelength.

Further, the respective lengths at the blue emission wavelength and the infrared emission wavelength obtained in step S50 are also

[0082]

(Equation 7)

It becomes Here, αB is the transmittance of the cloth at the blue emission wavelength obtained in step S45, VB '/ VB0 is the transmittance of the fluff at the blue emission wavelength obtained in step S15, and VB
B1 is the received light voltage when the solar cell 4b is fully opened at the blue emission wavelength.

Further, for the lower cloth, the cloth detection length and the fluff length are calculated in the same manner as described above.

Since the edge position x1 and the fluff portion x2 of the cloth can be detected in this way, even if the width of the fluff portion changes, the cloth is sewn with the seam allowance accurately provided at the edge of the cloth. It will be possible.

FIG. 10 shows an example in which a light emitting device (light source) is used instead of the surface emitting LED panel 3 shown in FIG. 3. In the example shown in FIG. 10, a rod-shaped LED array (red) 20a,
Rod-shaped LED array (green) 20b, rod-shaped LED array (blue) 20c and rod-shaped LED array (infrared) 20d
Is used for each of the rod-shaped LED arrays 20a to 20d.
Is arranged on one leg of the U-shaped block 20, and the solar cells 4a, 4b are arranged on the portions facing the leg. In each rod-shaped LED array, as shown in FIG. 11, chip-shaped LEDs are arranged at equal intervals, and the solar cells 4 facing each other are arranged.
A uniform light is obtained on b.

The structure of a circuit having this light emitter is shown in FIG. The circuit is the same as that of FIG. 4, except that the light emitters are rod-shaped LED arrays 20a to 20d, and the operation is the same as that described with reference to FIG.

Further, in FIG. 13, the surface emitting LED panel 3 is shown.
Wide directional LED (red) 22a, wide directional L
An example is shown in which an ED (green) 22b, a wide directional LED (blue) 22c, and a wide directional LED (infrared) 22d are used as light emitters. Each of these light emitters is placed far away from the solar cells 4a, 4b, which results in a substantially uniform illumination of the LED light on the solar cells, allowing a linear sensor output. Although this wide directional LED is one for each wavelength in this figure,
There may be a plurality of lines for each wavelength.

FIG. 14 shows the configuration of a circuit having these wide directional light sources, and FIG. 4 shows that the light sources are wide directional rod-shaped LED arrays 22a to 22d.
The operation is the same as that described with reference to FIG.

FIGS. 15A and 15B show surface emitting LEDs.
A light emitter that replaces the panel 3 is shown. In the example shown in the figure, the light emitter is a transparent light guide plate 25 made of acrylic resin or the like.
It is composed of a diffuse reflection plate 26 arranged on the back side of the light guide plate 25 and LED chips 3a arranged on both side surfaces of the transparent light guide plate 25. The LED chip 3a has a configuration in which R, G, B, and IR LEDs are sequentially arranged in a straight line. In this light source, the diffuse reflection plate 26 makes the illumination light uniform. Further, it can be made thinner than a surface emitting LED panel. The circuit configuration and operation are the same as in FIG.

FIG. 16 is a circuit diagram of FIG. 4 using a surface emitting LED panel, in which L is generated by the pulse output of the oscillator 10.
The circuit configuration is shown in which the LED is pulse-emitted by the pulse output of each emission wavelength from the microcomputer 17 rather than the ED being pulse-lighted. In this circuit configuration, the microcomputer 17 has the configuration shown in FIG.
When the flicker transmittance switch and the start switch are operated as shown in (b), (c) to (f) in FIG.
R (red) LED pulse r, G (green) LE as shown in
D pulse g, B (blue) LED pulse b, IR (infrared) L
The ED pulse ir is sequentially output to the signal lines 17a to 17d. An LED light emission timing signal is obtained for each pulse by the OR gate U9 (FIG. 17 (g)), and the pulse amount detection circuits 13a and 13b and the sample and hold 14a and 14b are driven in synchronization with this signal, respectively. ), The received light voltages VR ′, VG ′ detected by the solar cell for measuring the transmittance and the solar cell for measuring the cloth edge position,
VB ', VIR', VR, VG, VB, VIR and VRx, VGx,
VBx and VIRx are sampled and held. These values are read by the microcomputer 17 according to the read timing.
Read in, and as described in connection with the circuit of FIG.
The transmittance of the cloth and the fluff portion is calculated, and the cloth detection length and the fluff length are measured.

FIG. 18 shows a circuit obtained by simplifying the circuit configuration of FIG. This is a configuration in which the pulse amount detection circuits 13a and 13b for the measure against ambient light are removed from the circuit of FIG. When the surface emitting LED panel is close to the solar cells 4a, 4b and the amount of disturbance light is sufficiently smaller than the LED light, the configuration is effective. In this circuit, the microcomputer 17 operates the flash transmittance measuring switch and the start switch as shown in FIGS. 19 (a) and 19 (b), and as shown in FIGS. 19 (c) to 19 (f). R (red) LED and G (green) L via signal lines 17a to 17d
It outputs pulses to drive the ED, B (blue) LED, and IR (infrared) LED. The microcomputer 17 outputs the sampling signal as shown in FIG. 19 (g) at each pulse interval, and the sample & hold circuits 14a and 14b.
The output of the light quantity detector is sampled via
(H) to (k)). The subsequent operation is similar to that of the circuit of FIG.

FIG. 20 shows a structure in which the temperature sensor 19 is added to the structure shown in FIG. 4, and the surface emitting LED panel 3 and the solar cell 4a,
4B shows a circuit configuration for correcting the temperature drift appearing in the light amount detection voltage by 4b. The temperature drift is corrected by performing a correction operation on the light amount detection voltage input to the analog multiplexer 15 according to the temperature detected by the temperature sensor 19.

FIG. 21 shows a structure of the surface emitting LED panel 3 and the solar cells 4a and 4b in which the light amount detecting circuit 12c for monitoring the light amount of the surface emitting LED panel, the pulse amount detecting circuit 13c, and the sample & hold circuit 14c are added to the configuration of FIG. 2 shows a circuit configuration for correcting temperature drift and aging change appearing in a light amount detection voltage. Light amount detection circuit 12c, pulse amount detection circuit 13c, sample & hold circuit 14c
Are the light amount detection circuits 12a and 12b, the pulse amount detection circuit 1
3a and 13b, sample and hold circuits 14a and 14b
And a light amount detection circuit 12c, a pulse amount detection circuit 13c, and a sample & hold circuit 14c.
Light amount detection circuits 12a and 12b, pulse amount detection circuits 13a and 13b, based on the voltage obtained through the channel of
The light amount detection voltage obtained in each channel of the sample & hold circuits 14a and 14b is arithmetically corrected to correct temperature drift and secular change.

FIG. 22 shows a circuit configuration of another embodiment. In the circuit of FIG. 4, a light amount detection circuit, a pulse amount detection circuit, and a sample & hold are provided for the transmittance measurement and the cloth edge position measurement, respectively, and further the voltage values for the transmittance measurement and the cloth edge position measurement are set. Needed an analog multiplexer to switch. On the other hand, in the circuit of FIG. 22, the light amount detection circuit 12b and the pulse amount detection circuit 13
b, the sample and hold circuit 14b measures the transmittance and the cloth edge position. Similar to FIG. 4, a solar cell 4a for measuring transmittance and a solar cell 4b for measuring cloth edge position are provided, and a transistor Q for grounding these solar cells is provided.
20, Q21 are connected to each solar cell. When measuring the transmittance of the cloth and the fluff part, the microcomputer 17
The transistor Q20 is driven by the switching signal from the switch, and the transistor Q21 is driven at the time of measuring the cloth edge, and the light quantity detecting circuit 12b, the pulse amount detecting circuit 13b, and the sample & hold circuit 14b respectively measure the transmittance and the cloth edge position. Be done.

FIG. 23 shows another embodiment of the light emitter and the light receiver. In the embodiment shown in FIGS. 2 and 10,
Although the solar cell and the surface-emitting LED panel are closely opposed to each other, in the embodiment shown in FIG. 23, the light receiver 40 having wide directivity is used as the light receiver. The light receiver 40 is arranged apart from the surface emitting LED panel 3, and detects the amount of cloth covered on the surface emitting LED panel by the amount of light received by the light receiver 40. Multi-wavelength light emitting LED adjacent to the surface emitting LED panel 3
The panel 3x is arranged. The panel 3x is provided to measure the transmittance of the cloth and the fluff portion for each wavelength.

FIG. 24 shows a circuit diagram using the configuration of FIG. In the figure, the surface emitting LED panel 3
And the multi-wavelength LED panel 3x has a transistor Q22 driven by the microcomputer 17,
Q23 is connected, the transistor Q23 is driven to activate the multi-wavelength light emitting LED panel 3x during the transmittance measurement, and the transistor Q23 is activated during the cloth edge position measurement.
22 is driven. The operation is similar to that of the circuit of FIG.

FIG. 25 shows another embodiment of the light emitter and the light receiver. In this example, instead of the surface emitting LED panel 3 of FIG. 22, a rod-shaped LED array (red, green,
Blue, infrared) 20a, 20b, 20c, 20d are replaced by the multi-wavelength light emitting LED panel 3x and each wavelength (red, green,
Blue, infrared) LEDs 41a, 41b, 41c, 41d are used. Each wavelength LED 41a, 41b, 41c,
41d determines the transmittance of the cloth and the fluff portion for each wavelength. In this example, the rod-shaped LED array can be made thinner than the surface-emitting LED panel. The circuits and operations used are the same as in FIG.

Further, in each of the above-mentioned examples, the light source using the LED as the light emitting means is used, but the light source is not limited to this, and each color light source such as a laser light source or another light source capable of emitting multiple wavelengths is used. It may be used. Further, each wavelength filter may be used by using a single light source having multiple spectra, and a light emitting means capable of switching a plurality of emission wavelengths may be realized by switching the filters.

Further, in each of the above-mentioned examples, for example, a single crystal type solar cell (photodiode) is used as the light receiving means, but a polycrystalline type solar cell may be used, and particularly, a component such as a separating plate is used as a base. When a polycrystalline solar cell is formed, the light receiving element can be thinned.

Further, in each of the above-described embodiments, the method for obtaining the fluff length or the cloth detection length in relation to the measurement of the cloth edge position of the sewing cloth in the sewing machine has been described, but the present invention is not limited to this. INDUSTRIAL APPLICABILITY The present invention is also applied to the measurement of the lengths of heterogeneous portions having different transmittances at the end portions of a sheet-shaped object such as a film or paper and the end position of these objects.

[0102]

As described above, according to the present invention, the emission wavelength suitable for receiving the object is selected from the transmittance of the object, and the heterogeneous portion at the selected emission wavelength and the emission wavelength other than the visible light is selected. Since the length of the heterogeneous portion is measured based on each transmittance of the object and each received light amount from the object including the heterogeneous portion at the selected emission wavelength and the emission wavelength other than visible light, the heterogeneous portion is measured. Even if the length of the object changes, the end position of the object can be accurately detected.

[Brief description of drawings]

FIG. 1 is a side view showing a case where the device of the present invention is used for sewing a sewing machine.

FIG. 2 is an explanatory diagram showing a state in which the transmittance of a cloth and the position of the cloth edge are measured using a surface-emitting LED panel.

FIG. 3 is a partially cutaway perspective view showing a structure of a surface emitting LED panel.

FIG. 4 is a circuit diagram showing a circuit configuration for measuring the transmittance of the cloth and the fluff portion and the cloth edge position.

FIG. 5 is a flowchart illustrating the flow of measuring the transmittance of the cloth and the fluff portion and the cloth edge position.

FIG. 6 is a flowchart diagram following FIG. 5;

FIG. 7 is a flowchart diagram following FIG. 6;

8 is a timing chart showing the operation of the circuit of FIG.

FIG. 9 is an explanatory diagram illustrating detection of a length of a fluff portion and a cloth edge position.

FIG. 10 is a perspective view showing another configuration of a light emitter and a light receiver.

FIG. 11 is a layout view showing a detailed configuration of the light emitter of FIG.

12 is a circuit diagram showing a circuit configuration for measuring the transmittance and the cloth edge position of a cloth and a fluff part using the light emitter of FIG.

FIG. 13 is a perspective view showing still another configuration of a light emitter and a light receiver.

14 is a circuit diagram showing a circuit configuration for measuring the transmittance and cloth edge position of a cloth and a fluff part using the light emitter and the light receiver of FIG.

FIG. 15A is a perspective view showing another example of the light emitter.
(B) is a side sectional view thereof.

FIG. 16 is a circuit diagram showing a circuit configuration for driving a surface emitting LED panel by a switching signal from a microcomputer.

17 is a timing chart showing the operation of the circuit of FIG.

18 is a circuit diagram showing a circuit configuration in which a measure against ambient light is removed from the circuit configuration in FIG.

19 is a timing chart showing the operation of the circuit of FIG.

20 is a circuit diagram showing a circuit configuration that enables temperature compensation in the circuit configuration of FIG.

21 is a circuit diagram showing a circuit configuration capable of monitoring the amount of received light in the circuit configuration of FIG.

FIG. 22 is a circuit diagram showing a circuit configuration having a common channel for measuring the transmittance of the cloth and the fluff part and the measurement of the cloth edge position.

FIG. 23 is a perspective view showing still another configuration of a light emitter and a light receiver.

24 is a circuit diagram showing a circuit configuration for measuring the transmittance and cloth edge position of a cloth and a fluff part using the light emitter and the light receiver of FIG. 23.

25 is a perspective view showing another configuration of the light emitter of FIG. 23. FIG.

[Explanation of symbols]

 3 Surface emitting LED panel 4 Solar cell 4a Transmittance measuring solar cell 4b Cloth edge position measuring solar cell 7 Cloth 10 Oscillator 11 LED drive circuit 12a, 12b Light intensity detection circuit 13a, 13b Pulse amount detection circuit 14a, 14b Sample & hold circuit 15 Analog Multiplexer 16 A / D converter 17 Microcomputer

Claims (11)

[Claims] 1. An object for measuring an end position of an object by measuring an amount of received light from the object, which changes according to a change in an end position of the object having a heterogeneous portion with different transmittance at the end. In the measurement method of 1, a plurality of emission wavelengths are sequentially switched and projected onto an object, the transmittances of the heterogeneous part and the object are measured for each emission wavelength, and the light emission suitable for receiving the object from the transmittance of the object. Select the wavelength, and the transmittance of the heterogeneous portion and the object at the selected emission wavelength and the emission wavelength other than visible light, and the target object including the heterogeneous portion at the selected emission wavelength and the emission wavelength other than visible light A method of measuring an object, characterized in that the length of a foreign portion is obtained based on each received light amount from. 2. The method of measuring an object according to claim 1, wherein the emission wavelengths other than the visible light are infrared emission wavelengths. 3. The transmittance of the foreign part and the object is calculated from each ratio of the received light amount for each emission wavelength and the received light amount for each emission wavelength when there is no foreign part or object. The method for measuring an object according to claim 1 or 2. 4. The measurement of an object according to claim 1, wherein the object is a sewing object sewn with a sewing machine, and the foreign portion is a fluff portion. Method. 5. An object for measuring the edge position of the object by measuring the amount of light received from the object which changes in accordance with the change of the edge position of the object having a heterogeneous portion with different transmittance at the edge. In the measuring device, a plurality of emission wavelengths can be sequentially switched, a light receiving unit for receiving light of each emission wavelength from the foreign portion and the target object, and a light receiving amount of the light receiving unit from the foreign portion and the target object. Calculating means for calculating the transmittance for each emission wavelength, selecting means for selecting an emission wavelength suitable for receiving the target object from the calculated transmittance of the target object, and the selected emission wavelength and light emission other than visible light Measures the length of the heterogeneous part based on the transmittance of the heterogeneous part at the wavelength and each transmittance of the target, and the amount of light received from the target including the foreign part at the selected emission wavelength and the emission wavelength other than visible light It is equipped with Measuring device for target objects. 6. The object measuring device according to claim 5, wherein the emission wavelengths other than the visible light are infrared emission wavelengths. 7. The transmittance of the foreign part and the object is calculated from each ratio of the received light amount for each emission wavelength and the received light amount for each emission wavelength when there is no foreign part or object. The object measuring device according to claim 5 or 6. 8. The measurement of an object according to claim 5, wherein the object is a sewing object to be sewn with a sewing machine, and the foreign portion is a fluff portion. apparatus. 9. The light receiving means includes a first light receiver for receiving light from an object or a foreign part to obtain a transmittance, and an object including a foreign part to measure an end position of the object. The device for measuring an object according to any one of claims 5 to 8, which is configured by a second light receiver that receives light from an object. 10. The light emitting means includes a first light emitter that projects light having a plurality of emission wavelengths onto an object to obtain a transmittance, and a plurality of emission wavelengths to measure an edge position of the object. 10. The object measuring device according to claim 5, further comprising a second light emitter that projects the light of FIG. 11. The light emitting means comprises a light emitting diode that emits light of different emission wavelengths, and a driving means that sequentially pulse-drives these light emitting diodes. The measuring device for an object according to any one of 1.