JPH0461095B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is suitable for a spun yarn fuzz measuring device, especially a small and lightweight portable type, and can reliably measure the fuzz regardless of fluctuations in illuminance at the measuring location. The present invention relates to a fluff measuring device capable of measuring fuzz.

[Conventional technology]

The fluff measuring device for spun yarn regulates the traveling path of the yarn, irradiates light onto the fluffed portion of the yarn as it travels, magnifies the shadow of the fluff with a lens, and then enters a light receiver to measure the amount of incident light due to the shadow of the fluff. A typical example of this is described in Japanese Patent Publication No. 46-22182.

As schematically shown in FIG. 25, the device described in the above publication includes a projector 1 for projecting a shadow light image of the fluff of the running yarn 2, a slit plate 4 for projecting the fluff 3 of the yarn 2, and a slit plate 4 for projecting the fluff 3 of the yarn 2. An optical lens 5 that prevents diffusion of the shadow light image, a light receiver 6 provided in the focal region of this optical lens 5, an amplifier 7 that amplifies the fluff detection signal from this light receiver 6, and a fluff output from the amplifier 7. The number of shadows of the fluff 2 passing through the front surface of the light receiver 6 is counted and displayed as the number of fluffs of the yarn.

However, as mentioned above, such a fluff measuring device is structured so that the number of changes in the amount of received light that changes each time the shadow of the yarn fluff passes the front surface of the light receiver is measured as the fluff count, so it is difficult to install the measuring device. If the environmental illuminance at the location has small fluctuations, no measurement error will occur, but if the illuminance at the measurement location changes, the amount of light incident on the light receiver will fluctuate, reducing the reliability of the measured values.

This inconvenience is solved as described in Japanese Patent Publication No. 56-26313, in which the light is applied to the emitter according to the amount of light received so that the amount of light that enters the receiver after receiving the output of the receiver becomes a predetermined constant amount. This can be improved by providing a voltage control circuit (dimmer).

[Problem to be solved by the invention]

However, even in a fluff measuring device equipped with such a light control device, in addition to the light from the emitter, other light (external light) that can be seen at the installation location of the measuring device is also incident on the light receiver. As the amount of light increases, the voltage applied to the emitter will drop significantly, resulting in significantly less light coming from the emitter, and in extreme cases, no light will be emitted from the emitter, making it impossible to detect fluff. There was a problem that the reliability was greatly reduced, if not impossible.

The present invention has been made in order to solve such problems, and is capable of performing reliable fluff measurement without changing the voltage applied to the projector even when the amount of external light fluctuates. The purpose is to provide a measuring device.

[Means to solve the problem]

In order to achieve the above object, the fluff measuring device of the present invention uses a low-pass filter that removes a fluff signal consisting of a high frequency component corresponding to fluff in a fluff detection signal, and an inverter that inverts the input signal. A first signal from which the fluff signal has been removed and a second signal that is opposite in polarity to this signal and includes the fluff signal are formed, and these first and second signals are combined by an adder. The signal obtained by the addition is input to the counter, and a correction power supply is provided to adapt the level of the input to the counter to the operating level of the counter.

[Effect]

In the fluff measuring device configured as described above, by adding the first signal and the second signal, the variation due to external light contained in the first signal and the second signal is calculated. are canceled out, a fluff signal is extracted, and a correction power supply adapts the level of this fluff signal to the operating level of the counter.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

Fig. 1 is a diagram schematically showing a fluff measuring device according to an embodiment of the present invention, Fig. 2 shows the main part of the embodiment of Fig. 1, and Fig. 2A shows the configuration of this main part. Figure 2B is a diagram showing the waveform of the output signal of each component in Figure 2A, and Figure 3 is a diagram showing a specific example of the circuit in Figure 2A. Reference numerals are given and explanations thereof are omitted.

In the figure, 9 is a low-pass filter, 10 is an inverter, and 11 is an adder, all of which are connected between the photodetector 6 (consisting of a phototransistor in the illustrated embodiment) and the counter 8. connected,
Further, a correction power supply 12 for adding a constant voltage is further connected to the adder 11. The low-pass filter 9 is connected to the output of the photoreceiver 6 and removes high frequency components (fuzz signal) corresponding to fuzz in the output voltage (fuzz detection signal) of the photoreceiver 6. The input signal (in this embodiment, the output voltage of the light receiver 6) is inverted and output. The low-pass filter 9 and the inverter 10 are connected in parallel between the light receiver 6 and the adder 11. Note that 13 indicates a branch point on the output side of the light receiver 6.

Next, the operation will be explained.

The waveform of the output voltage (fuzz detection signal) of the light receiver 6 is shown as V ₁ in Fig. 2B, and this output voltage V ₁
enters the low-pass filter 9, where high frequency components (fluff signals A, B, C) corresponding to the fluff 3 are removed and output as the first signal _V2 . The output voltage V ₁ of the photoreceiver 6 also enters an inverter 10 , which contains the fluff signals A, B, and C as they are, but whose polarity has been inverted with respect to the first signal V ₂ . A second signal _V3 is output. The first signal V ₂ and the second signal V ₃ are added by an adder 11, and a constant voltage V ₄ is added to this added signal by a correction power supply 12 to generate the high frequency component, that is, the fluff 3. A signal obtained by adding a constant voltage to only the corresponding signals A, B, and C (hereinafter referred to as counting signal _V5 ) is output from the adder 11, and is input to the counter 8 and counted.

Here, the constant voltage V ₄ of the correction power supply 12 is determined by the counter 8
The size is selected to meet the minimum operating level of the The heights (amplitudes) of the fluff signals A, B, and C are determined by the fluff thickness because the thickness of the fluff is almost constant (almost constant in the case of synthetic fibers, and almost constant in the case of cotton). is approximately proportional to the length of Therefore,
The heights of the fluff signals A, B, and C vary depending on the length of the fluff, as shown in FIG. In the fourth case, three fluff signals A, B, and C are illustrated, and in this case, the length of the fluff is C>A>B. Then, assuming that the fluff signal corresponding to the shortest fluff to be measured (those shorter than that are not measured as fluff) is B, the constant voltage V ₄ of the correction power supply 12 is the range of the amplitude H of the fluff signal B. The minimum operating level L of the counter 8 is selected to fall within the range. That is, V 4 is adjusted so that the conditions of V ₄ <L and L < V ₄ +H, in short, the conditions of L-H < V ₄ <L are satisfied _.
Select. If V ₄ <L, in other words V ₄
If ≧L, the counter 8 always operates with only the voltage _V4 and does not respond to the fluff signals A, B, and C. In addition, if L−H<V ₄ , in other words, V ₄ +
This is because if H≦L, the counter 8 will at least not respond to the fluff signal B. Therefore, for example, if the minimum operating level of the counter 8 is 3V and the amplitude of the lowest fluff signal B to be measured is 0.3V, then V ₄ is set in the range of 2.7V < V ₄ < 3V. Become.

In this way, the first signal V ₂ and the second signal V ₃ have opposite polarities, so even if the output voltage V ₁ of the light receiver 6 fluctuates due to fluctuations in the amount of external light (this fluctuation (best shown as a variation in the first signal V ₂ ), this variation is canceled out in adder 11 . Further, the first signal V ₂ is the fluff signals A, B,
C is removed, whereas the second signal V ₃
includes the fluff signals A, B, and C, so even if the first signal _V2 and the second signal _V3 are added, the fluff signals A, B, and C remain without disappearing, and the correction power supply 12 This ensures that the fluff signals A, B, C are matched to the lowest operating level of the counter 8 and counted by the counter 8.

5 and 6 show other embodiments of the invention, FIG. 5 being the same as FIG. 2 of the previous embodiment, and FIG.
The figure is similar to FIG. 3. This example is the first
The difference from the embodiments shown in FIGS. 3 to 3 is that a low-pass filter 9 and an inverter 10 are connected in series between a light receiver 6 and an adder 11, and the output of the light receiver 6 is connected to a low-pass filter 9 and an inverter 10. and the inverter 10 are connected in parallel to the adder 11, and in this embodiment, the fluff signals _A ,
The signal V 2 obtained by inverting the signal V ₆ obtained by removing B and C with the low-pass filter 9 with the inverter 10 constitutes the above-mentioned first signal V ₂ , and the output voltage of _the photodetector 6
V ₁ directly constitutes a second signal V ₃ (which has the opposite polarity to the first signal and includes fluff signals A, B, and C), and these first and second signals are added by an adder 11. Further, the level is increased by the constant voltage _V4 from the correction power supply 12. Also in this embodiment, the first signal V ₂ and the second signal V ₃ have opposite polarity,
Since only the second signal _V3 includes the fluff signals A, B, and C, the addition in the adder 11 cancels out and removes the effects of fluctuations in the amount of external light, while only the fluff signals A, B, and C are extracted. Similarly to the embodiments shown in FIGS. 1 to 3, the voltage of the extracted signal is increased in level. In this embodiment as well, the constant voltage V of the correction power supply 12 is adjusted so that the lowest operating level L of the counter 8 falls within the amplitude range of the fluff signal B input to the counter 8, as shown in FIG. ₄ is selected, but in this embodiment, the fluff signals A, B, and C are downward, unlike in the embodiments shown in FIGS. 1 to 3, so the voltage V ₄ is L. <V ₄ <L+H. Therefore, as in the case of Fig. 4, L=3V,
If H=0.3V, the voltage _V4 of the correction power supply 12 is 3V<
It will be set within the range of V ₄ <3.3V.

Still other embodiments of the invention are shown in FIGS. 8 and 9, in which FIG. 8 is similar to FIGS. 2 and 5 in the previous embodiment, and FIG. 9 is similar to FIGS. and a diagram similar to FIG. 6. This embodiment differs from the embodiments shown in FIGS. 5 and 6 only in that the positions of the low-pass filter 9 and the inverter 10 are reversed.
It is similar to the embodiment shown in the figure, and its operation is also similar.

In each of the above embodiments, the addition of the first signal and the second signal and the addition of the constant voltage V ₄ of the correction power source 12 are performed using one adder 11, but two adders are used. may be used to separately perform the addition of the first signal and the second signal and the addition of constant voltage.

10 and 11 show a first embodiment using two adders. That is, in the figure, 11A is a first adder, and 11B is a second adder. In FIG. ₃ is added with the constant voltage V ₄ from the correction power supply 12 in the first adder 11A to obtain a level-up signal (V ₃ +V ₄ ), and this signal (V ₃ +
V ₄ ) and the low-pass filter 9, the fluff signals A, B,
The first signal _V2 from which C has been removed is added to the second adder 11.
B is added so that a counting signal _V5 having the same shape as that of the embodiment shown in FIG. 2 is outputted.

12 and 13 show a second embodiment using two adders, which as in the embodiment of _FIG .
V ₃ is added in the first adder 11A, and a constant voltage V ₄ is added in the second adder 11B to the obtained signal (V ₂ + V ₃ ) of only the fluff signals A, B, and C to obtain a counting signal. It is designed to output _V5 .

Another example using two adders is shown in the first example.
This is shown in FIGS. 4 to 19. Figures 14 and 15
The figure shows the third embodiment, FIGS. 16 and 17 show the fourth embodiment, and FIGS. 18 and 19 show the fifth embodiment. Next, the low-pass filter 9, the inverter 10, and the first adder 11A are connected in series, and the first adder 1
By connecting the correction power supply 12 to 1A, a first signal _V2 from which the fluff signals A, B, and C are removed is formed, and this signal _V2 is raised in level by the constant voltage _V4 of the correction power supply 12. A signal (V ₂ +V ₄ ) is formed, and this signal (V ₂ +V ₄ ) is added to a second signal V ₃ containing fluff signals A, B, and C from the light receiver 6 in a second adder 11B. The third, _fourth , and fifth embodiments are different from each other in the low-pass filter 9, the inverter 10, and the first adder 11A. Since the operation is completely the same except for the connection order of the series connection, the explanation thereof will be omitted.

Another example using two adders is shown in the second example.
0 to 23. Figures 20 and 21
The figure shows the sixth embodiment, and FIG. 22 and the second embodiment.
FIG. 3 shows a seventh embodiment, and in each of these embodiments, the first adder 11A first adds the first signal V ₂ and the second signal V ₃ to obtain the signal (V ₂ +
V ₃ ) and take out only the fluff signals A, B, and C, and in the second adder 11B, the fluff signals A, B, and C are extracted.
The constant voltage V ₄ of the correction power supply 12 is added to B and C to obtain the counting signal V ₅ .
This shows that various connection points of B can be selected. In short, the adder for adding the constant voltage V ₄ of the correction power supply 12 may be placed anywhere between the branch point 13 and the counter 8, and for example, the adder in FIGS.
In the embodiment shown in FIG. 2, the second adder 11B and the correction power source 12 may be moved to the location indicated by the dashed line. Similarly, in the embodiments of FIGS. 10 and 12, the second adder 11B and the correction power source 12 may be moved to the light receiver 6 side of the low-pass filter 9 or to the opposite side.

One of the major features of the present invention is that the constant voltage of the correction power supply 12 is set such that the minimum operating level of the counter 8 falls within the amplitude range of the fluff signal with the lowest amplitude to be counted (in the above embodiment, the fluff signal B). Generally speaking, the amplitude of the fluff signals A, B, and C is not very large, and especially when trying to measure very short fluff, it is necessary to set the voltage of the correction power supply ₁₂ with high precision. The embodiment shown in FIG. 24 solves this problem. That is, in the embodiment shown in FIG. ₁ is inverted and amplified to increase the amplitude of the fluff signals A, B, and C, and this inverted amplified signal _V8 is branched into a circuit for a first signal _V2 and a second signal _V3 , and one circuit is In addition, a voltage follower 1 is installed to stabilize the signal voltage.
4. First adder 11A connected to correction power supply 12;
Inverter 10 and low-pass filter 9 are connected in series,
After adding the constant voltage V ₄ to the inverted and amplified signal V ₈ , it is re-inverted by the inverter 10 , and then the low-pass filter 9 converts this re-inverted signal into fluff signals A,
By removing B and C, the signal (V ₂ +V ₄ )
This signal (V ₂ +V ₄ ) and the second signal V ₃
are added in the second adder 11B, and then inverted and amplified again in the inverting amplifier 15 to obtain a counting signal.
It is configured to obtain V ₅ , and the reliability of the fluff count value by the counter 8 can be further increased.

〔Effect of the invention〕

Since the present invention is configured as described above, fluctuations in the amount of external light are canceled out by addition in the adder without changing the voltage applied to the projector, so even if the amount of external light increases, the change in the amount of external light is canceled out by the addition in the adder. The light intensity does not decrease, and the level of the signal is increased by the correction power supply so that the level of the fluff signal matches the minimum operating level of the counter, so the reliability of fluff counting is much higher than that of conventional methods. You can get better effects.

[Brief explanation of drawings]

FIG. 1 is a diagram schematically showing an embodiment of the fluff measuring device according to the present invention, FIGS. 2 and 3 are diagrams showing the main parts of the embodiment of FIG. 1, and FIG. A block diagram showing the configuration of the main parts, FIG. 2B is a diagram showing the waveform of the output voltage of each component in FIG. Figures 5, 6, and 7 are diagrams showing other embodiments of the present invention, and are similar to Figures 2, 3, and 4 of the aforementioned embodiments, respectively. Figures 8, 9, and 10
Figures 11, 12 and 13, 14 and 15, 16 and 17
18 and 19, 20 and 21, 22 and 23, and 24.
The figures are diagrams showing various different embodiments of the present invention, respectively.
Figure 16, Figure 18, Figure 20, Figure 22,
Figure 24 is the same diagram as Figure 2 above, Figure 9
Figures, Figure 11, Figure 13, Figure 15, Figure 17,
FIG. 19, FIG. 21, and FIG. 23 are similar to FIG. 3, and FIG. 25 is a diagram schematically showing a conventional fluff measuring device. In the figure, 1 is a floodlight, 2 is a thread, 3 is a fluff,
6 is a light receiver, 8 is a counter, 9 is a low-pass filter,
10 is an inverter, 11 is an adder, 12 is a correction power supply,
V ₁ is a fluff detection signal, V ₂ is a first signal, V ₃ is a second signal, V ₄ is a voltage of a correction power supply, and A, B, and C are fluff signals. Note that the same reference numerals in each figure indicate the same or equivalent parts.

Claims (1)

[Claims] 1. A light projector that projects light onto the fluff portion of the running yarn, a light receiver that receives the light that has passed through the fluff portion and generates a fluff detection signal corresponding to the amount of light, and a high frequency component of the fluff detection signal that corresponds to the fluff. A fuzz measuring device comprising a counter for counting the number of fuzz signals consisting of a low-pass filter connected between the light receiver and the counter to remove the fuzz signal from the fuzz detection signal, and an input signal. a first signal from which the fluff signal has been removed by the low-pass filter and the inverter;
A second signal having a polarity opposite to that of the first signal and containing the fluff signal is provided, and an adder is provided for adding the first signal and the second signal, and the output of the adder is Connected to the counter, and shifting the fluff signal so that the lowest operating level of the counter falls within the amplitude range of the lowest amplitude fluff signal to be counted among the fluff detection signals input to the counter. A fluff measuring device characterized by being equipped with a correction power source.