CN101713634A

CN101713634A - Eccentricity meter for wires and cables and method for measuring concentricity

Info

Publication number: CN101713634A
Application number: CN200810161966A
Authority: CN
Inventors: R·利文斯顿
Original assignee: BETA LASERMAC
Current assignee: BETA LASERMAC
Priority date: 2008-10-06
Filing date: 2008-10-06
Publication date: 2010-05-26

Abstract

An eccentricity meter for wires and cables and a method for measuring concentricity measures the position of a conductor within an insulating sheath using three measurement planes, at least one of which is capable of determining the conductor position and at least one of which is capable of determining the position of the peripheral edge of the outer sheath.

Description

The method that is used for the eccentricity gauge of electric wire and cable and is used to measure concentricity

Technical field

The present invention relates to be used to measure the concentricity of cable or wire and the system of diameter.Particularly, the present invention relates to be used for the concentricity of non-contact measurement cable or wire and the system and method for diameter.

Background technology

During insulated cable and electric wire manufacturing, people wish to guarantee that conductor (for example, tinsel) accurately is in the center that covers insulating material wiry.In order to measure its concentricity, way is location and the periphery that quantizes insulating material the most easily, measures the position of conductor wherein then.

For the discussion here, conductor is made by the internal material of conduction.Outer sleeve comprises insulating material.Both combinations are called cable.Difference between these two positions of conductor center and outer sleeve center is defined as degree of eccentricity.

It is useful using non-contact measurement device measuring cable when cable forms, because when it leaves extruder, insulating material is warm, soft and easy the damage.Typically, optics or magnetic equipment are used for this purpose.During forming process, cable in extrusion longitudinally constant speed move.Because also experiencing laterally, the vibration in the described tinsel, cable move.Historical way is to measure the diameter of outer insulator and the position of conductor in the same point along cable axis, to obtain the best readings of degree of eccentricity.

Current idea is to use optics and Magnetic Measurement device, and these devices are positioned on the same measurement plane perpendicular to the cable longitudinal axis.Current, it is believed that if measurement plane is in the different position along cable axis, the actual degree of eccentricity of distinguishing cable still is that angular deviation will be very difficult.Measurement mechanism will be measured at one time, otherwise cable may laterally move in the time interval, measures thereby destroy.

Equipment before a kind of shown in No. 5528141, the United States Patent (USP) of Kyriakis discloses a kind of optical flat and Magnetic Measurement plane, and mentions on tinsel the identical point place and measure, but need not measure simultaneously in same level.Another equipment shown in No. 7068359, the United States Patent (USP) of Studer discloses two magnetic transducing coils that are arranged on the optical flat both sides.Coil links together, their connected mode makes them form the single Magnetic Measurement plane consistent with the optical measurement plane, and determine and be mutually related field intensity before and after the optical measurement plane of field intensity, with definite active measurement of inductance plane consistent with the optical measurement plane.This design is to measure at single time reference.

Prior art still needs to improve.The present invention has improved prior art, and a kind of new-type system is provided, and this system is placed on measuring equipment in the independently isolated vertically zone, so that a kind of reliable measuring system to be provided, and allows to increase the space of maintenance, repairing and cleaning member.

Summary of the invention

One object of the present invention is to improve the measuring system of cable or wire.

Another purpose is to improve and is used to measure the degree of eccentricity of cable or wire and the non-contact measurement of diameter.

Another purpose is to be provided for the three point measurement systems that separate out vertically of cable or wire.

Another purpose is to provide the method for determining the position of tinsel in cable.

In the present invention, desirable is that optics and magnetic sensor are placed in the different measurement planes.This has alleviated the narrow short environment of measured zone, and provides the space for light beam and magnetic detector.This has also improved the ability that keeps sensors clean in originally with regard to dirty and environment need dust guard and air nozzle in narrow zone.

Accordingly, one aspect of the present invention relates to a kind of device, and this device is used to measure substantially the degree of eccentricity and the diameter of the elongated object that moves along the z axle.Described device comprises along isolated in the axial direction at least three the discrete measuring equipments of z axle, each equipment can obtain the object measured value in the different measuring plane at z axle predetermined point place in order to storage, wherein each plane is with respect to z axle (for example, vertical) orientation at a predetermined angle.These measured values can obtain at given predetermined instant with for the x-y point place of object area measure to be measured.According to these three groups of coordinates, degree of eccentricity can be determined and be used for from predetermined point derivation measured value.Can adopt computer based equipment to receive and store measurement values and definite degree of eccentricity.For example when measurement comprises the cable of insulating sleeve and inner wire, at least one equipment can be measured the diameter that position wiry and equipment can be measured sleeve pipe, and all the other equipment can be used to measure the diameter of tinsel or sleeve pipe.

Described device can comprise for example four kinds of different configurations, and arranges with one of four kinds of different configurations:

Two optical devices form the plane on the both sides of the magnetic apparatus that forms the magnetic plane;

Two optical devices form the plane on a side of the magnetic apparatus that forms the magnetic plane;

Two magnetic apparatus form the plane on a side of the optical device that forms optical flat; Or

Two magnetic apparatus form the plane on the both sides of the optical device that forms optical flat, wherein said equipment is orientated and makes described plane keep common angle with respect to cable when cable moves.

The present invention also is provided for measuring substantially the degree of eccentricity of the elongated object that moves along the z axle and the method for diameter.The present invention includes step: (a) adopt along isolated in the axial direction at least three the discrete measurement mechanisms of z axle, make each device can obtain the object measured value in the different measuring plane at z axle predetermined point place, wherein each plane is with respect to z axle (for example, vertical) orientation at a predetermined angle; (b) when movement of objects, obtain measured value with each equipment, obtain three groups of x-y-z coordinates in object zone to be measured thus at given predetermined instant; (c) use these three groups of coordinates to determine the degree of eccentricity of object; (d) calculate the diameter of object according to the degree of eccentricity of gained.This method can be preferably used for measuring cable or wire.

Description of drawings

Figure 1A is the perspective schematic view of the embodiment of the invention.

Figure 1B is the perspective schematic view of the embodiment of the invention.

Fig. 1 C is the perspective schematic view of the embodiment of the invention.

Fig. 1 D is the perspective schematic view of the embodiment of the invention.

Fig. 2 shows the perspective schematic view on three different measuring planes.

Fig. 3 shows the vertical view of optical measuring apparatus of the present invention.

Fig. 4 shows the vertical view of magnetic field induction measuring equipment of the present invention.

Embodiment

Referring now to accompanying drawing,, apparatus and method of the present invention are generally by Reference numeral 100,100 ', 100 " and 100 " ' expression, and be particularly suited for measuring for example degree of eccentricity and the diameter of cable 4.Parts like the similar Reference numeral representation class.During extruding (extrusion) process, cable 4 is under the tension force, thereby is straight line basically.From mathematics, 2 limit straight line in the space, and therefore, if a people measures 2 points simultaneously, such as 2 points on outer sleeve 9 or the inner conductor 3, he will know the position of the axis (z axle as illustrated in fig. 1 and 2) of cable 4.

The present invention can adopt the known biaxial optical mircrometer gauge of electric wire and cable

industrial circle

7,8, so that measure diameter by accurately measuring by the shade of light beam projection.Typically but not necessarily,

light beam

15x and 15y are arranged to each other in the right angle, and cable 4 and two light beam quadratures and pass this cross section.The light beam that intersects has been set up the x-y measurement plane, one of them light beam 15x measurement of x coordinate, and another light beam 15y measures the y coordinate.Typically but not necessarily, cable 4 passes measurement plane 13 orthogonally.

In one case, the present invention can adopt a pair of biaxial

optical mircrometer gauge

7,8 of spaced apart certain distance, can determine that outer sleeve 9 is along the position in two measurement planes of the z axle of cable 4.These points define the axis as the insulative cylinders body of space line.By measuring the position of inner conductor 3 in the 3rd plane (the 3rd plane does not overlap with two described optical flats), can determine how far conductor 3 has from the space line of previous foundation.Conductor 3 has determined degree of eccentricity from the distance that previously defined straight line departs from.

In practice, the spatial order of measurement is unimportant, as long as along the z axle at least three measurement point p1, p2 and p3 are arranged, the mixing of optics and Magnetic Measurement mode is arranged, and they is getting final product of adopting simultaneously for this purpose.Like this,

Magnetic Measurement plane

11 and 12 can be positioned at the both sides or a side on optical measurement plane 13, or under the situation of using two optical measurement planes, these optical measurement planes can be positioned at the both sides or a side on Magnetic Measurement plane.Measure inner conductor 3 and measure in single the 3rd plane under the situation of outer sleeve 9 in two planes, the order of measurement plane can have multiple.

The design that the present invention sets up is: use the three-dimensional of the z axis of cable 4 to be defined as the space line that limits into by two measurement points, and detect the distance that the 3rd measurement point arrives this straight line, determine it from the distance of this straight line as degree of eccentricity.In addition, the design that the present invention determines is, conductor central axis z is described as a space line from the mathematics angle, and this straight line is limited by the position of two Magnetic Measurement point p1 and p2 (for example being the point of crossing of conductor 3 and two

horizontal survey planes

11 and 12).This straight line is extrapolated from mathematics, pass the some p 3 on the 3rd parallel optical measurement plane 13, wherein, four points 10 on the periphery that is in insulating sheath or sleeve pipe 9 are being arranged on the optical measurement plane 13 measured to predict it.Distance between the point of extrapolation and the geometric center of four optical measurement points has determined degree of eccentricity.

For simplicity, the 3rd preferred arrangements is only described; Promptly two Magnetic Measurement equipment are positioned on the side of optical flat.This is shown in Figure 1A.The description of other three kinds of layouts is similar.

According to this layout, in order to measure degree of eccentricity, equipment at first must be set up the space line z that the center limited by conductor 3, and how far the center of measuring the periphery of outer sleeve 9 then has from the straight line of being set up.

In order to set up first spatial point, this device 100 can adopt be arranged in the vertical substantially plane 11 of the z axle of cable 3 in one group of four magnetic field sensor 5 and 6.The induction alternating current is to set up resonance magnetic field in conductor 4.

Such magnetic field increases along with the distance with the axis z of conductor and reduces, thereby allows

sensor

5 and 6 to measure the position of conductors 3.Preferably,

sensor

5 and 6 is arranged in couples on the relative both sides of cable 4 in the plane 11, thereby, determines the nominal straight line indication of the position of conductor in specific plane 11 by a signal is deducted another signal.Like this, these two pairs of

sensors

5 and 6 are arranged so that in plane 11 can set up x and y position, and the z axle then is the axis of cable 4.Cable 4 roughly is positioned at the center on plane 11 and from four

sensors

5 and 6 roughly

equidistant.Sensor

5 and 6 can be a sensing coil (being sometimes referred to as detecting coil), maybe can be the chip upper sensor (sensor on chip) of any kind of (magenetorestrictive) that is called magnetoresistance, magnetostrictive (magnetostrictive) or hall device.In order to form the magnetic field of measuring for these sensors, excite cable 4 with alternating current by means of certain external current source (not shown) preferably from the sensing apparatus of a distance of the present invention.

Intensity by measuring two x sensors 5 also deducts another amplitude from an amplitude, conductor can be summed up as a numerical value at the position measurements of x axle dimension.Similarly, use two y sensors 6 to determine the y position.X and y coordinate so just on Magnetic Measurement plane 11, have been set up.

In order to set up second point, the

magnetic sensor

5 and 6 of identical set is positioned at along the z axle away from first group of

sensor

5 and 6 one than short distance, and is arranged in the plane 12 that is basically parallel to first plane 11.Identical with the metering system of front, the position at its center when x and y component have determined that conductor 3 passes this second plane 12.Define the center of the conductor 3 in this device uniquely along these two groups of x-y components of the spaced apart certain distance of cable axis z.

Like this, two unique some P1 and P2 in two

parallel planes

11 and 12, have been determined, this just sets up a unique space line L, and this space line L will be unique but the 3rd measurement plane 13 that is basically parallel to preceding two

planes

11 and 12 is passed at unmeasured some P 3 places, as shown in Figure 2.By extrapolation, can predict the position of this P3 in the 3rd plane 13.The 3rd measurement plane 13 is equipped with optical measuring apparatus shown in Figure 37 and 8.What for example, the optical measuring apparatus in the plane 13 can be in two types is a kind of.These equipment are known by the people in industry, are known as " photograph meter (camera gauge) " and " scanner ".They are generally used for measuring the diameter of cable or wire, but also can be set to the measuring position.These two types all have the projected light beam projection to object under test, and measure the size of shade with the typical sub-micron class precision.When such equipment configuration has two to intersect light beams, x and y position that they can Measuring Object.

The position of four points 10 on the circular periphery basically of

optical device

7 and 8 definite insulating material or sleeve pipe 9.The geometrical mean of four points 10 is the unique points 14 in the 3rd measurement plane 13.In Fig. 3, the optics in the 3rd measurement plane 13 determines that the distance between point 14 and the extrapolation point P3 is exactly a degree of eccentricity.This is exactly the center of this conductor relevant with the insulator center basically.

The position of three measurement planes can be relative to each other, and predicts the coordinate figure of the point in the 3rd plane 13 to help every pair of point in preceding two measurement planes 11 and 12.Bare wire or not insulated metallic filaments be to be close to perfect concentric cable, nominally because its insulation course is zero.If tinsel can reach the straight degree of making, these three planes just can be associated by means of measuring the x-y position of bare wire in each of three planes.Non-linear for correcting measuring equipment, the data of collecting a plurality of positions of cable 4 and angle are just enough.Collected data comprise the x-y position of bare wire in three

planes

11,12 and 13.Can carry out least square fitting in view of the above and form equation, this equation can be mapped to the 3rd point the plane from every pair of point on two planes of beginning.Computer based equipment 50 is operably connected to

sensor

5,6,7 and 8, and is equipped with the software that is used to carry out calculating operation described herein.Sensor can be surveyed absolute amplitude or angle as used herein, to determine the position.

Be used for determining the degree of eccentricity of cable or wire and the more dynamic method and the measurement mechanism of diameter by these products being provided, the invention provides.In addition, when measuring cable or wire, the invention provides the environment of easier work, maintenance and repair.

Claims

1. An apparatus for measuring the eccentricity and diameter of an elongate object moving substantially along the z-axis, said apparatus comprising:

at least three discrete measurement devices, said at least three discrete measurement devices being axially spaced apart along said z-axis such that each device can obtain for storage an object in a different measurement plane at a predetermined point in the z-axis measurements, wherein each plane is oriented at a predetermined angle with respect to the z-axis, and each said device is equipped to obtain stored measurements of the object at a given predetermined time instant and actual x-y coordinates; and

A computer-based device operatively connected to said measuring device, said computer-based device having software means to receive and store said three sets of actual measured coordinate values, using two sets of said actual coordinates value to derive the third set of predicted coordinate values, and calculate the eccentricity by calculating the difference between the third set of predicted coordinate values and the actual third set of coordinate values.

2. The device for measuring the eccentricity and diameter of an elongated object moving substantially along the z-axis according to claim 1, wherein said object is a cable comprising an insulating sleeve and an inner wire, the first Said device is capable of measuring a wire diameter, a second said device is capable of measuring a casing diameter, and a third said device is capable of measuring one of a wire diameter and a casing diameter.

3. Apparatus for measuring the eccentricity and diameter of an elongated object moving substantially along the z-axis according to claim 1, wherein at least one of said devices comprises an optical measuring device and one of said devices comprises Magnetic measuring equipment.

4. The apparatus for measuring the eccentricity and diameter of an elongated object moving substantially along the z-axis according to claim 3, further comprising two optical devices, said two optical devices forming a magnetic Flat surfaces are formed on both sides of the magnetic device.

5. The apparatus for measuring the eccentricity and diameter of an elongate object moving substantially along the z-axis according to claim 3, further comprising two optical devices, said two optical devices forming a magnetic A plane is formed on one side of the magnetic device.

6. The apparatus for measuring the eccentricity and diameter of an elongated object moving substantially along the z-axis according to claim 3, further comprising two magnetic devices, said two magnetic devices forming an optical A plane is formed on one side of the optical device.

7. The apparatus for measuring the eccentricity and diameter of an elongate object moving substantially along the z-axis according to claim 3, further comprising two magnetic devices, said two magnetic devices forming an optical Flat surfaces are formed on both sides of the optical device.

8. A method for measuring the eccentricity and diameter of an elongate object moving substantially along the z-axis, said method comprising the steps of:

(a) Employ at least three separate measurement devices axially spaced along the z-axis so that each device can obtain measurements of the object in different measurement planes at predetermined points on the z-axis, where each plane is relative to the z-axis the axis is oriented at a predetermined angle;

(b) taking measurements with each device at a given predetermined time while the object is moving, thereby obtaining three sets of x-y coordinate values of the area to be measured of the object; and

(c) Using the three sets of coordinate values to determine the eccentricity of the object.

9. The method of claim 8, wherein the object is a cable.

10. The method of claim 8, further comprising performing step (c) using a computer-based device.

11. The method of claim 8, wherein step (a) is characterized by equipping said discrete measuring device to obtain said measurements for storage, and further characterized by that step (c) comprises using a A computer-based device of software processes the coordinate values to determine eccentricity.

12. A method for calculating the position of a conductor within an insulating sheath, said method comprising the steps of:

(a) using at least three measurement planes, at least one of which is capable of measuring the position of the inner conductor to derive a first set of coordinate values for the first plane, and at least one of which is capable of measuring the position of the outer sheath for deriving the second set of coordinates for the second plane. one set of coordinate values, the remaining planes being able to measure one of the position of the outer sheath and the position of the inner conductor to derive a third set of coordinate values in a third plane; and

(b) deriving a predicted set of coordinates in said third plane in said plane using said first set of coordinate values and said second set of coordinate values, and combining said predicted set of coordinates with said third set of coordinates Values are compared to determine the eccentricity and position of the conductor within the sheath.