DE1548207A1 - Method and device for measuring the diameter of wires or the width of narrow strips using light beams - Google Patents

Description

Society with 'Friedrichstr. 38

■ limited liability Dr. "Ke / Ba files Div.

Ϊ548207

Method and apparatus for measuring the diameter of wires or the width of narrow ribbons by means of light rays

• They are used to measure the diameter of wires or the width of narrow ribbons by means of light beams Methods and devices have already become known, according to which the continuously moved in the longitudinal direction-e Workpiece influences the light beam path in an electro-optical device in such a way that the respective width or the respective diameter of the workpiece triggered proportional electrical impulses and be registered.

After this, the entire width or the diameter of the workpiece is mapped with the aid of a lens and the image scanned by an electrical detector, which has the disadvantage that the respective measured value with a fluctuating distance between the workpiece and the one in the device Lens changed to an unacceptable degree.

In order to counter this deficiency, it is proposed according to the invention that the one already influenced by the workpiece Light beam path through a moved perpendicular to the axis of the workpiece across its width or diameter System of at least two centered to each other, each except for a small opening closed shutters to feel through, these

if? knife of the workpiece to be measured.

Opening is small compared to the width or the diameter

• «ν. In the case of cold ^{workpieces or workpieces that do not emit light rays, the latter effect the influence of ω} light radiation in such a way that they interrupt the light of a light source and cast a shadow, while in the case of glowing workpieces the natural light radiation over the

BAD ORfGINA] L

electro-optical device the triggering of electrical impulses "causes the builder of the respective Width or the respective diameter of the workpiece is proportional. The one in one system centrally arranged diaphragms are normally parallel to one another; however, they can also, for example when using mirrors, should be appropriate in intersecting planes.

In the case of a two-panel system, simultaneous Achieving an intensification of the light radiation the method proposed according to the invention change so that the light radiation through a lens facing the workpiece instead the one panel and through the other panel, which is centrally located behind it, is passed in such a way that that a small area lying in the plane of the workpiece is sharp in the range of the permissible depth of focus is shown in the aperture of the aperture.

As a device for performing the above method proposed according to the invention, the diaphragm or diaphragm lens system perpendicular to the axis of the continuous To arrange workpiece and about an axis running parallel to the axis of the system, preferably on a circular path to make it movable.

t It has proven to be advantageous to have a around its axis rotatable bell with one or more, arranged in its shell, on the circumference preferably evenly distributed diaphragm or diaphragm lens systems with a fixed underneath Use the base plate located on the bell, one or more on the same circle Like the systems, openings that are also preferably evenly distributed over the circumference of the circle for the entry of light rays.

909840/0737

BATH ORIGINAL

Instead of a circular or otherwise curved movement of the diaphragm or diaphragm lens systems it is of course also easily possible to do the latter periodically over the workpiece in another way respectively.

With the invention proposal is achieved that error by shifting the workpiece in a vertical view, that is, in the direction of the measuring device towards or away from it were largely avoided. Only by moving the workpiece to the side measurement errors can still occur. In order to avoid this too, the invention is being developed further the additional arrangement of a trigger with subsequent correction circuit suggested-

The exemplary embodiments shown schematically in the drawing are used for further explanation.

Fig. 1 is a device for carrying out ' the method according to the invention;

2a-c show a further development of the device according to FIG. 1;

3a, b relate to another further development the device according to Fig.

According to the embodiment of FIG, 1 are in the jacket of a bell 1 at the same distance from each other, three diaphragm lens systems 2 ', 2 ", 2'" arranged, in each of which there is a lens 2a at its lower end and a diaphragm at its upper end 2b together with a coupling 8a for one end of a light guide 5. A motor 4, the axis of which Bell carries and lets it rotate, is on a base plate 7 with a recess A for the beam path attached. The other end of the light guide 5 is close to the center of the head plate 1 a Bell on a small circle with the

.909840 / 0737

BATH

154 8ZU /

other light guides of the other two systems their other ends open into couplings 8b, attached. The light guides transmit the from the in the direction of the arrow Moved workpiece or wire 3 influenced or emitted light rays on one in the head plate 6a of a mounted on the base plate 7 attached housing 6 detector 11, the electrical Signal amplified and rectified in an electronic device 9 and by a measuring instrument 10 is displayed.

As an extension of the measuring method according to the invention, a further recess A is shown in FIG diametrically opposite recess B is provided.

k This means that the workpiece is scanned more frequently and one

greater differentiation of the diameter along the workpiece is achieved. The main advantage of the This is achieved, however, lies in the measured value · ^ changes due to vibrations of the wire in a to be able to compensate for a plane lying perpendicular to the system axis.

With each pass one of the systems 2 ', 2 ", 2' · ' In front of the recesses A and B, a square pulse is generated when the wire is passed over. In the pig. 2b are the impulses plotted in their chronological order. The wire vibrates in both directions of the double fe arrows to and fro between the dashed borders,

so the widths of the impulses are changed. If the system and wire have the same direction of movement, Q the pulse longer; if they run against each other, the to pulse is shorter. For example, if the wire swings so that its

oo

.p- movement in A coincides with the scanning direction, so

^ the pulse 2 ¹ A is lengthened. When the system ° 2 "passes through B, the wire will still have the same direction of movement, so that the pulse 2" B becomes shorter. (See Fig. 2c). The mean value of the two pulses, which is formed in the detector 11, then has no or a significantly reduced error as a result of the wire oscillations.

FIGS. 3a and b "relate to a further development the measuring device, which largely eliminates measuring errors caused by lateral displacement of the workpiece ". For this purpose, as shown schematically in the figure, a Trigger is used, which is at position 12.

The trigger arrangement can be designed in such a way that there is a small one on the head plate 1 a of the bell 1 Magnet and located in the plate 6a of the housing 6 located above it, an inductive pickup. Every time when the magnet passes the inductive pick-up, the pick-up emits a voltage signal that for example, may have the shape of a triangular pulse J-η. With This signal controls a gate which is closed again by the leading edge of the measuring pulse J ^ so that a sequence of correction impulses Jg- arises. The time between opening and closing the gate, i.e. the length of the correction pulses, corresponds to this Paths of the system between the trigger point 12 and the beginning of the wire and gives when the wire diameter is known the change in position of the wire in relation to this trigger point. If one integrates the correction impulses, so one obtains a DC voltage signal that. proportional to the path between the trigger point and the start of the wire is. The DC voltage is fed to a small unit in which it is converted into the correction variable and this is then added to the final DC measurement signal obtained, depending on the position of the wire or is subtracted.

It should also be noted that in addition to inductive triggers, other electronic-optical or mechanical Triggers can be used.

9 0 9 8 4 0/0737 bad ORfQJNM,

Claims (5)

1 R L ft 9 Π 7 claims ^ 1) "Method of measuring the diameters of wires or the width of narrow belts, the workpiece being continuously moved in the longitudinal direction affects the light beam path of an electrical-optical device in such a way that electrical Pulses are triggered and registered, their duration of the respective width or the respective Diameter of the workpiece is proportional, characterized that the already influenced light beam path through a perpendicular to the axis of the workpiece over whose width or diameter moving system of at least two centered to each other, each except for one opposite the width or the diameter of the workpiece to be measured small opening of closed apertures is passed through. 2) Method for measuring the diameter of wires or the width of narrow bands, j under the action of light radiation of a continuously moving in the longitudinal direction glowing workpiece electric an electrical-optical device can be triggered I see pulses and registered (the duration of the the respective width or the respective diameter of the workpiece is proportional, j characterized in that the light radiation of the workpiece is caused by a system of at least two centered to one another, which is moved perpendicular to the axis of the workpiece over its width or diameter. is passed through each except for one, compared to the width or the diameter of the workpiece to be measured, small opening of closed apertures. 909840/0737 ^BAD original 3) Modification of the method according to claim 1 or 2 in the case of a two-panel system, characterized in that the light beam path or the light radiation through a lens facing the workpiece instead of one diaphragm and through the other centered behind the aperture is passed in such a way that a small one in the plane of the workpiece The lying surface is shown in focus in the area of the permissible depth of focus in the aperture of the diaphragm will. 4) device for performing the method according to claim 1, 2 or 3, characterized, that the aperture system or aperture-lens system perpendicular to the axis of the workpiece passing through arranged and around an axis running parallel to the axis of the system, preferably on one Circular path, is movable. 5) device according to claim 4,
marked by a bell (1) rotatable about its axis with one or more diaphragms or diaphragm lens systems (2 ¹ , 2 ", 2 '") arranged in its casing, preferably evenly distributed around the circumference, and a fixed underneath the bell Base plate (7) with one or more lying on the same circle as the systems, also preferably on the circumference of the circle co evenly distributed openings (A, B) for the jv. Light beam entry. ^α 6) Device according to claim 4 or 5, co characterized by ^ ³ additional arrangement of a trigger with subsequent gender correction circuit for the purpose of taking into account the effects of a parallel displacement of the workpiece conditional error. BAD ORSGIMAL Blank page