DE1952630A1 - Apparatus for checking the edge of flat materials - Google Patents

Description

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Applicant: ~ * ~ Ludwigshafen / Rh ·, 16 · 10.1969

Giuseppe Piattelll P 4697 I / * l _Q

Montecatini Terme - I y 04O JU • (Italy)
Via Torino 9

Representative;

Patent attorney

Dipl.-Ing. Adolf H. Fischer
Ludwigshafen / Rhine
Richard-Wagner-Strasse 22

Apparatus for checking the edge of flat materials

The invention "relates to an apparatus for controlling of the edge of flat materials, such as fabric., sheets, tapes, sheets and the like and consists in that a control head is provided, the at least one Group of! Photocells ('photosensore'), in connection with a light source, through which at least a path is definable which is intended to slide along the edge which is being controlled, wherein further the group has means for shielding the external light, a signal being given at the exit, which varies depending on the refraction of light at the edge by changing the light beam emanating from the light source is interrupted while an electronic circuit, triggered by on the edge of the sheet or the like «arranged Mechanics and / or signaling devices, has means,

- 2 008817/1471

to continuously transform and amplify the signals to apply them at the right time,

also facilities around the time of reinforcement to vary these facilities, namely the triggering of the setting and the coil calibration of the device in Depending on the properties of the material to be controlled, facilities to automatically set the average Determine the speed with which these devices come into operation and finally devices to to avoid accelerating these facilities too quickly

Another embodiment of the invention provides that in the electronic circuit devices are provided to the uninterrupted, equal signals so transform so that these serve for the constant transmission of a quantitative threshold value.

Another proposal of the invention is that in the electronic circuit a servomotor is provided to to remove the initial unbalance

. According to another proposal of the invention one goes so before that in the electronic circuit the entry signal controls a threshold circuit, going first to the amplifier, this circuit having a number of interchangeable ones Diodes, because the system has an arbitrarily adjustable loosener to various To be able to vary the spark between fields that are too small and too large,

. According to the invention you can also proceed so that a 'linear amplifier is provided by using of an integration circle a © slight variation »

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'BAD ORIGINAL

availability of the amplified sound. .

Another proposal of the invention provides that A special generator (dinometacogeneratore) is associated with the engine, doing dynamic compensation of mechanical vibrations and is connected to an electrical chain that switches them off during periods of constant higher speeds.

According to the invention, the switch (attuatore) is fed from the signals emanating from the amplifier including Relays, actuated selectively by these signals, and causes active and inactive regulating devices to adjust the edge and / or the signaling.

Another design according to the invention provides that each photocell (photosensor # receives a light beam, which crosses a system that consists of a transparent and / or filtering and / or polarizing wall and an optieahen path, capable of doing so the room light% te & U8, while parallel to the direction ' the light beam Sh between the optical path and the corresponding photocells (photo sensors) optical capacitors are set to distribute the light evenly on the photo resistors.

According to a further embodiment of the invention contains The control head has two identical groups of photocells (fetosensors') that form a single central one Light source are allocated.

According to the present invention, each photo resistor can be instantaneously be adjacent to another photo resistor and receive the light from the central light source passing through the corresponding passage goes through a system consisting of a transparent and / or filtering and / or polarizing wall and a plurality of optical plastics (fiber ottiche).

According to the invention you can also proceed so that the Control head contains a group of photocells (photosensors), the wave frequencies, including those that lie outside the visible spectrum, translate into electrical signals that photocells (photosensors) of the Light source are attached and with this a strip designed to slide along the edge of the material to be checked, these photocells (photosensore) are an image converter or photo transistor and are connected to an electronic circuit that Contains means to take from the outside the essentials of the intensity of the light beam, accordingly the various opacity or properties of the material and further facilities around the Initial coil calibration, depending on this bearing, to be carried out, with the electronic circuit includes an amplifier consisting of an integrated microcircuit, with variable gain, on its Output are the first devices mentioned above, formed by a voltmeter with a central zero point, also the devices that contain a potentiometer whose integrated circuit can be replaced by another is to make the coordination with the special photocells (photosensors), according to the bandwidths used for the respective material Spectrum frequency. .

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Another embodiment of the invention provides that the control apparatus is equipped with fields of different wavelengths, the one assigned to the direction finder optical condenser can be replaced by a hollow electrical stub line (condotto cavo tronco-conico), by internal surface reflection around the light rays entering the web against the small base of the To center the line where the direction finder is located

The apparatus according to the invention gives the possibility of using its own control system to determine the edges of flat To control formed, very generally speaking, Regardless of whether it is a sheet, a sheet, a fabric or the like, the big advantage is it is given that this control does not have any directives Contact with the edge to be checked is necessary, so that a universal use results · The invention. Apparatus can also z. B-. then used when it comes to punched edges, or similarly formed *, or when it comes to materials acts, e.g. B. sheet, which should be checked at higher temperatures, what with the known means is difficult to design.

The apparatus according to the invention can also be used to control the edge of any material, regardless of whether it is transparent or opaque

In the various types of known apparatus used for such controls, the various difficulties arising from the Interaction of the facilities used there result, namely photoresistors or photodiodes or mechanical or pneumatic devices. ·. "

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Such devices are used in a wide variety of industries, e.g. B *. in the textile industry around the edges of tissues * or their precise introduction into any further processing machines. Man previously used pendulum suspension for this purpose Feelers that feel the edge of the fabric. It is known that the edges of fabrics are not always the same, so that ' it is therefore very difficult to carry out an inspection in such a way, especially when it is is a light fabric. The use of pneumatic sensors _ is always excluded if the Ge-P weave is light, especially if it is permeable to air. There are also such devices that help with work from powder, using the changes in light, temperature or the like for control ι be. This z. B. in the paper industry, in printing, ■ in the iron industry and various others. In the latter Apparatus has already been used several times, which work using magnetic effects, but which kick here very often disadvantages in that magnetic fields persist in an undesirable form.

In the accompanying drawings, some examples of the design of the apparatus according to the invention are shown in schematic sketches.

Show it,

Figure 1 is a schematic view of a design

an apparatus according to the invention, in which the control head contains two groups of photocells (photosensors),

Figure 2. a similar view as in Figure 1 ,.

Figure 3 - a scheme of an electronic circuit »as z. B-. be used in the heads according to Figure 1 or Figure 2,

Figure 4 · a variant of the * scheme shown in Figure 3, ■

FIG. 5 shows another possible design of the control head, which contains a single group of photo cells (photosensors) and

FIG. 6 shows a diagram of the electronic circuit in the control head according to Figure 5 "

In Figure 1, an embodiment of the invention is one KontidLlkopfes 12 shown mounted on a carrier 1 and which has a central group of light emitters 2, for example with internal lamps, which are between two parallel transparent or translucent plates 3 are arranged through which two identical light beams pass. 'Parallel to this and at a short distance, in this way a narrow one. Forming passage two groups are more identical Protective walls 5 are provided, which can consist of white glass or a colored shield, so that they if necessary are able to filter the light rays and then only the passage for those rays of the spectrum allow, for which the assigned photo resistor 7 has the highest sensitivity. Between the wall 5 and the photo resistor 7 are a number of steel disks provided, which are arranged parallel to the light beams so that they form an optical row 4-, in this way prevent interference from external light. An optical capacitor 6 is used for the light

to bring the photo resistor 7. Between one of the two spaces that arise between the walls 3 and, the pattern 9 »z. B. a sheet, a tape od. The like. Introduced, it is brought into such a position that it can serve as a reference sample, while ¹⁵ od in the other space of the edge of the sheet control is.

The pattern 9 is attached to a carrier 10 which is adjusted from the outside with the aid of a threaded spindle 10a • I can be used to set pattern 9 in genes can bring that is needed for the edge of the sheet 8. In the variant according to FIG. 2, the control head is I2a essentially the same. The phototransistors 7 & are attached to the carrier la in a different position, which serves the purpose of ii the closest possible distance of the two photo resistors to arrange. The Elements 2, 3 and 5 are provided in the same places, but the light that passes through the discs 5 on the Photo resistors 7 & penetrates in this case a larger number of optical plastic threads 21 (fiber ottiche).

As for the electronic circuits that are attached to the control head 12 or 12a, it is shown in FIG. 3 that a circle with a boundary for the control of the Has provided rotation of a motor 17, with the aid of a remote switching device; in Figure 4 it is shows that a group of amplifiers is provided at the output to control a servo motor which is connected to stands with a special generator (dinometacogeneratore).

The function of a control head 12 or 12a, the

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corresponds to the embodiments described here first, is based on the use of two identical twin groups that contain two photo resistors 7 or 7a, which are connected in series and are fed with constant .. voltage of absolutely the same value, but with reversed signs, in such a way that their common point 11, due to the same lighting, of photocells 7 or 7 * leads to zero potential The opposite case if the two photo resistors 7 and 7 & are illuminated differently at their common point 11, a positive or negative voltage will result, depending on whether one of the two photo resistors is illuminated more or less. The whole facility will then work like a Wheatstone bridge, whose two branches are formed by the photo resistors 7 or 7a are. Such variations in the lighting of the photo resistors by controlling the strip of any material 8 result from possible differences in the formation of this edge to be checked with regard to the formation of the pattern 9 · The photo resistors 7 or 7a are with a resistive isolator connected, which has the task of balancing the two photo resistors.

The control head 12 or 12a gives signals to the if necessary Threshold circuit 13 formed from a series of diodes suitably selected and connected. If the system is equipped with an adjustable loosener that allows it to be adjusted as required, so you can then choose a more affordable series Diodes to be able to turn on, 'im . Change to reduced or very large fields.

At de, m circle 14 a signal of the same kind is through going to a linear amplifier 14, the signal so

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reinforces that it becomes more decisive, which serves to control level 15. This is a complementary one j Stage N.F.NfP.N.F., whose charge the collectors of the J both terminal transistors concerned by the windings are given by two Beiais. Then when the signal is on the base of the two transistors, be it positive or negative, is given, one or the other of the ' Relay energized and at the same time the remote switch 16 the pulse to the motor 17, so that with the help of the control this relay the 'one movement or the other of these organs is initiated in order to regulate the position of the belt 8, which is carried out in the most varied of ways can be and is not specially shown.

The puncture of the apparatus proceeds as follows:

You set a sample 9 of the material, which controls * should be, and sets with the help of the thread spin. del 10a the position of the pattern 9 as needed, accordingly the preselected position of the edge of the material j The sheet 8 runs through in the space and covers it the connected photo resistor 7, which also makes the pattern 9 identical. When the positions of the . j cover both edges in line 11, then W will not have any Signal go out, and both the motor 17 and all other control organs remain at rest. In the reverse Case, a positive or negative potential will arise at this point, depending on the rope's rope Edge of the material 8 depending on the position of the pattern 9. In such a case, the line a signal go to the threshold circuit 13, which depends on the type of material to be examined • The signals amplified by the amplifier 14- are thus capable of the stage lf> to put into action

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-lies that s one or the other of the relay is switched, z. Serve as relative to the deviations of the correction of the edge, weeping other similar devices to perform the correction of the position _t of the sheet 8 or other similar operations.

Various devices which are brought into effect by the switched-on amplifier 14 can bring about an increase or a decrease in the response time, starting from the displacement of the edge 8 and the resolution of the correction in order to avoid sudden * variations in the setting impede.

Due to the tax gain of the system, one can use the The voltage of the charging of the bridge of the photo resistors vary, but you can also get the Amplifier determine the amplitude of the field, given by the freedom of the edge of the sheet 8 or the like.

it should be noted that the whole system is proportional, i. i.e., by every infinitesimal shift of the At the edge, proportional variants of the output signal result, which can be used directly for ongoing control of the Course of the edge can be used.

According to the variants of the circles that belong to cells Ϊ2 or 12a (Figure 4), the line gives a signal to a preamplifier 18, with the aid of dynamic stabilization elements, the signals being a power output amplifier 19, connected to an adapter 20, which has a motor or a phase element 17a controls, which is connected to a special generator 22 (dinotacogeneratore) to compensate for the vibration of the whole system.

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A design, as shown in Figures 5 and 6, requires a slightly modified form of the control head. This head 112 contains a single group of photocells (photosensors). With such a design, the material 8 to be checked can be opposed to a pattern 9, or the difference in exposure that is generated with such a material 8 by "a light bundle" compared to that which produces an identical light bundle 9 on the pattern 9 can be used When locating and reading the possible differences, it is advantageous to cut out the instruments _# with appropriate special calibrations. The special generator 22 (dinotacogeneratore), as it is provided in the variant according to FIG System to balance in order to guarantee the intended function and thereby also to ensure a certain slowing down of the examination of the edge.

In the design shown in Figures 5 and 6 the control head is one of those, the one with a broad The belt works with a capacity that is used to control materials that, as a result of various opacity, different. Have wavelengths. "and is connected to a special electronic circuit, provided with an integrated microcircuit, which is directly connected, with a voltmeter 111 with a central Zero point, which enables the observer to read the correction of the extraction directly, depending on of the material to be tested, with the help of a potentiometer. On the other hand, the electric chain is for them Compensation of the electrical and mechanical system in this embodiment equipped so that the Vibrations of the group are dampened ^ with the help of the Effect of the tachogenerator suddenly occurring

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ORIGINAL INSPECTED

- 13- · Accelerations of the mechanical system.

In Figure 5, the control head 112 is shown, which of carried on a carrier 110; a light source 102 lies below a plate 103 * through which the light rays go through, wherein in combination the plate is provided that is transparent, filtering or polarizing is, so that there is a gap into which the edge of the sheet to be checked, sheet or the like can be. Here, too, an optical row is provided and for the concentration of the light frequency on the photo cells (photosensors) a capacitor 106, as which in this case an image converter or phototransistor 107 is provided which has a certain amount of Absorbs light, proportional to the actual penetration of the material under control and which causes a signal to be sent to the electrical circuit which is shown in FIG. 5 on block 109 and is illustrated in Figure 6 by a schematic of blocks; a circle that is in a container is housed, under the cover plate the command device 110 of the potentiometer of the adapter of the Circle and the indicator screen 111 with the central zero.

The circuit 109 includes an amplifier 14-a connected is connected to a loader 23, with the outputs to a control circuit 24 and to a motor GVC. 17b are connected via a group of differential reactors for the speed and the acceleration 35 · Between the command circuit 24 · and the motor 17b a power level 25 is interposed, the Motor 17b controlled by a tachometer generator 20a is. This embodiment of the invention works as follows:

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In the gap of the control head 112 is the to be checked Material carried out which of larger or lower opacity, which triggers a stronger or weaker signal from the image converter 107, these signals being applied to an amplifier 14a consisting of an integrated Microcircuit exists with different extraction, the output of which with a voltmeter 111 with a central zero point connected is. This voltmeter allows the instant -Reading the difference value of the examined material, adjusting the system by correcting the Obtaining with the help of the potentiometer 110 allows and the correction by the instrument 111 on the. Head 112 is controllable.

You will also have to control materials more often, with long shafts, for which you can use the devices described above, z. B. using group 112 by removing protective cover 105. The shielded elements have an absorption spectrum in the field of frequencies of interest, whereby a conical reflective hollow body can also be exchanged for the condenser 106, whereby the light emission can be concentrated on the vertex, where the image converter 107 is also arranged. It can be noted that the particular electrical chain causes the system to be damped in the sudden accelerations, the frequency of the tachometer generator 20a being modified as a function of the magnitude of the accelerations. '

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Claims (12)

-. - 15 - s ~ l patent claims 1) \ Apparatus for the control of the edge of flat materials , such as fabric, sheets, tapes, sheets and the like, characterized in that a control head is provided , the at least one group of photo cells (photosensors) in connection with a light source, by means of which at least one path can be determined which is intended to slide along the edge which is being controlled , the group further comprising means for shielding the external light, a signal being given upon exit , which varies depending on the refraction of light at the edge , in that the light beam emanating from the light source is interrupted, while an electronic circuit triggered by mechanisms and / or signaling devices arranged on the edge of the sheet or the like has means for moving the signals to transform and reinforce in order to apply them at the right time, also facilities to determine the point in time when these facilities are strengthened conditions to vary, namely the triggering of the setting and the flush calibration of the device depending on the properties of the material to be checked, devices to automatically determine the average speed with which these devices come into operation and finally devices to accelerate these devices too quickly avoid. 2) Apparatus according to claim I _1, characterized in that devices are provided in the electronic circuit to transform the uninterrupted identical signals so that they are used for the constant transmission of a quantitative threshold value. - 16 - Ö6fii1? / 14? T - ΐ 3) Apparatus according to claim 1, characterized in that. "'·" A servomotor is provided in the electronic circuit to remove the initial unbalance. 4 ·) Apparatus according to claim 1, characterized in that the entry signal in the electronic circuit Threshold circuit controls, going to the amplifier first, this circuit being a series with each other has interchangeable diodes, because the system has a freely adjustable loosener, in order to be able to vary different points between too small and too large fields. 5) Apparatus according to claim 1, characterized in that a linear amplifier is provided by using an integration circuit allows easy variability of the gain. 6) Apparatus according to claim 1, characterized in that is associated with the motor a special generator (dinometacogeneratore), to achieve the dynamic compensation of the mechanical vibrations and ^reasonable: closed is connected to an electrical chain, they off. switches during periods of constant higher speeds. 7) Apparatus according to claim 1, characterized in that the on-switch (attuatore) fed by the "signals starting from the amplifier including Heiais, is selectively actuated and caused by these signals active and inactive regulating devices for adjustments with regard to the edge and / or the signaling. 8) Apparatus according to claim 1, characterized in that each photocell (photosensors) receives a light beam, • that crosses a system, daa made of a transparent and / or filtering and / or polarizing wall and an optical path capable of shielding room light while parallel to the Direction of the light rays between the optical path and the corresponding photocells (photosensors) optical capacitors are set to equalize the light * to be distributed moderately on the photo resistors. 9) Apparatus according to claim 1, characterized in that the control head has two identical groups of photocells (photosensors) that are assigned to a single central light source 10) Apparatus according to claim 1 and 9, characterized in that each photo-resistor directly to another - Photo resistor is adjacent -and the light from the central light source obtained by the corresponding Passage goes through a system that consists of a transparent and / or filtering and / or polarizing wall and a plurality of optical · plastics (fiber ottiche). 11) Apparatus according to claim 1 to 8, characterized in that that the control kqf a group of photo cells (photosensors) • Contains the wave frequencies, including those outside the visible spectrum, in Electrical signals translate that photo cells (photosensors) are attached to the light source and with this form a strip designed to slide along the edge of the material to be inspected, - 18 - These photocells (photosensors) are an image converter or photo-transistor and are connected to an electronic circuit which contains devices to receive from the outside the essentials of the intensity of the light beam, according to the different opacity or the properties of the material and furthermore Means to carry out the initial coil calibration as a function of this bearing, wherein; the electronic circuit includes an amplifier which ^; consists of an integrated microcircuit, with variable gain, at the output of which are the first devices mentioned above, formed by a voltmeter with a central zero point, furthermore the devices containing a potentiometer, the integrated circuit of which can be replaced by another, in order to coordinate with the make special photocells (photosensors) according to the bandwidths of the spectrum frequency used for the respective material. 12) Apparatus according to claim 1 and 11, characterized in that that the apparatus for control with fields of different Wavelengths is equipped, the direction of the direction finder arranged Optical condenser can be replaced by a hollow electrical * stub line (condotto cavo tronco-conico) is, through internal surface reflection, around those entering the web Rays of light, against · the small base of the Focus line where the direction finder sits. @ 0 S117 / 14? 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