US3207125A - Apparatus for measuring and controlling the amount of size and finish applied to textile yarns and fabrics - Google Patents

Description

Sept. 21, 1965 Filed July 23, 1962 C. F. STRANDBERG, JR

APPARATUS FOR MEASURING AND CONTROLLING THE AMOUNT OF SIZE AND FINISH APPLIED TO TEXTILE YARNS AND FABRICS D.C.Power 3 Sheets-Sheet l INVENTOR CHARLES F. STRANDBERG,Jr.

/7 7 I 1 BY 7? A cw ATTORNEY Sept. 21, 1965 c. F. STRANDBERG, JR 3,

APPARATUS FOR MEASURING AND CONTROLLING THE AMOUNT OF SIZE AND FINISH APPLIED TO TEXTILE YARNS AND FABRICS Filed July 25, 1962 I5 Sheets-Sheet 2 T 2| D.C.Power 20 p 42 6V.AC ll5V.A.C. l9

3 33$ K INVENTOR l LI CHARLES F. STRAND/BERGJL E BY ATTORNEY Sept. 21, 1

Filed July 23, 1962 C. F. STRANDBERG, JR APPARATUS FOR MEASURING AND CONTROLLING THE AMOUNT OF SIZE AND FINISH APPLIED TO TEXTILE YARNS AND FABRICS 5 Sheets-Sheet 3 |OO I Constant 34 Pressure 35 Air Supply I 31 Pneumatic j Controller 32 I INVENTOR CHARLES F. STRANDBERG,Jr.

ATTORNEY United States Patent 3,207 ,125 APPARATUS FOR MEASURING AND CONTROL- LING THE AMOUNT OF SIZE AND FINISH APPLIED TO TEXTILE YARNS AND FABRICS Charles F. Strandberg, Jr., Greensboro, N.C., assignor to Strandberg Engineering Laboratories, Inc., Greensboro, N.C., a corporation of North Carolina Filed July 23, 1962, Ser. No. 211,508 6 Claims. (Cl. 118-4) The present invention relates to a method and apparatus for continuously measuring and controlling the amount of size or finish material applied to textile yarns and fabrics in a slasher or other coating machine.

Before textile warp yarns are woven into fabric, they are usually slashed or sized, a process which applies a starch to the yarns for the purpose of protecting them against the abrasive actions of the loom.

Similarly, various finished compounds, including size, are added to woven and knitted fabrics for the purpose of increasing weight, surface quality, and durability in use.

The sizing and finishing processes are generally the same. The web is immersed in a liquid bath containing starch or some other compound. It is then passed between squeeze rolls, which extract the excess liquid, and on to a dryer section, which evaporates the water portion but leaves the starch or finish solids in or attached to the warp yarns or fabric.

Knowledge and control of the percentage of solids added to the web are very important, but there has been no satisfactory known method for continuously measuring it. Samples of the web, at present, must be cut out and applied to chemical separation processes, one of which is commonly known in the industry as de-sizing, in order to determine the percent solids added to the net weight of the web. These tests require considerable time to conduct, and the resulting information cannot be used during processing when it is needed most.

Several factors are known to affect the amount and consistency of the solids picked up. One of these is the percent solids in the liquid bath. This can, of course, be controlled by mixing desired amounts of dry solids with water in preparing the liquid bath. Another factor is squeeze roll pressure. Variations in the amount of liquid left on the web after squeezing cause corresponding variations in the solids retained after evaporation of the water portion in the dryer section.

Various other factors are contributory. Variations in viscosity and temperature affects solids pickup. These are often held constant for the purpose of reducing variations in pickup. The moisture content of the dry web, its velocity through the liquid bath and squeeze rolls, and the kind of fibers making it up also influence solids pickup.

As a means for determining approximate pickup over a period of time, some mills gauge the volume of liquid consumed against the weight of web processed. With this knowledge of the percent solids in the liquid, they are able to calculate the average solids pickup. The method is, again, time consuming and does not provide any information about the instantaneous pickup.

Some work has been done with electric capacitance measuring devices, which indicate the approximate weight of entering web and the dried web. Except for differences in moisture content, the difference between input weight and output weight is equal to the solids added. Due to the influence of moisture content upon the capacitance measurement, the method is not known to have been satisfactorily applied in a practical installation.

The measurement method employed in the apparatus of this invention utilizes the measurement of the liquid 3,207,125 Patented Sept. 21, 1965 added to the web. Since the percentage of solids in the liquid are usually known and controlled by regulated mixing procedures, it follows that the net solids picked up are in the same manner related to the total liquid picked up by the web. The relationship holds true, since the solids form a known part of the homogenous liquid, the relative parts of which are unchanged by squeezing.

The measurement on the web is made directly after squeezing prior to any evaporation due to drying. The effect of drying is, of course, to upset the known relationship between water and solids by evaporating the water portion without affecting the solids.

It is an object of the invention to provide a method and means for continuously measuring the amount of liquid added to the textile yarn or web in a slasher or other coating machine.

It is a further object of this invention to provide means to automatically control the amount of liquid added to the textile yarn or web according to the deviation of the measured amount of added liquid from a predetermined desired quantity of added liquid.

It is a further object of this invention to provide electrical conductivity measuring means for measuring the electrical conductivity of textile yarn or web after it has been treated with a treating liquid and indicating means for indicating the amount of added liquid determined as a function of the electrical conductivity of the treated yarn or web.

It is a further object of this invention to correct the electrical conductivity measurement of the liquid treated yarn or web in accordance with variations in the electrical conductivity of the treating liquid.

It is a further object of this invention to provide improved motor control means for automatically regulating the amount of treating liquid added to the material to be treated.

It is to be understood that the use of the term conductivity in this text has reference to electrical conductivity even though the word electrical is omitted.

With the foregoing objects and features in view and such other objects and features as may become apparent as this specification proceeds, the invention will be understood from the following description taken in conjunction with the accompanying drawings, wherein like characters of reference are used to designate like parts, and wherein:

FIGURE 1 is a diagrammatic representation of a textile finishing machine and the apparatus for measuring the amount of finishing liquid applied to the textile yarn or fabric with manual means for setting in a correcting factor for the conductivity of the finishing liquid.

FIGURE 2 is similar to FIGURE 1 but includes automatic means for setting in a correcting factor providing for variations in the conductivity of the finishing liquid.

FIGURE 3 is a diagrammatic representation of one form of apparatus provided for automatically controlling the pressure of the squeeze rolls of the slasher used in this invention.

FIGURE 4 is a diagrammatic representation of another form of apparatus provided for automatically controlling the pressure of the squeeze rolls of the slasher used in this invention.

Referring to FIGURE 1, untreated web 1 travels from the beam 2 over the guide roll 3 into the sizing liquid 4 in tank 5 and under the immersion roll 6. The web 7, now soaking wet with liquid, passes between the squeeze rolls 8 and 9. After squeezing, the excess liquid has been removed from the web, the weight of which has increased 50 to 200 percent due to the added weight of the liquid. The wet web 10 then contacts detector roll 11, one of the measuring elements of the instrument, and passes over a set of hot dry cans 12, which cause the water portion of the liquid on and in the web to evaporate. The speed of 3 .he machine and the surface temperatures of the dry cans are set so that the moisture in the web 13 is about the same as prior to processing. The sized or finished web is then wound on beam 14.

The apparatus described in the paragraph above with the exception of detector roll 11 is included in conventional slashers known in the textile industry.

The measuring circuit of this invention, consisting of a pair of spaced detector electrodes including grounded squeeze roll 9and detector roll 11, the portion of the size treated web 10 contacting and intervening the grounded squeeze roll 9 and detector roll 11, variable resistor 15, current limiting resistor '16, and the 6.3 volt transformer 17, is basically an A.C. conductivity measuring circuit. The two position switch 18 is a standardize-operate switch having two fixed contacts 18a and 18b engaged by the movable arm 18. Contact 18a is connected in a standardize circuit including a pair of spaced electrode probes 38 and 39 immersed in the liquid 4, the secondary Winding 21 of transformer 17, current limiting resistor 16, variable resistor and the movable contact 18'. The function of the standardize circuit is to enable adjustment of the variable resistor 15 in order to correct the measuring circuit for the conductivity of the liquid 4 in the tank 5.

Contact 18b is connected in a measuring or operating circuit, including the metal detector roll 11, the length of liquid moistened web or yarn 22, between roll 11 and roll 9, the grounded metal squeeze roll 9, the secondary winding 21 of transformer 17, resistor 16, variable resistor 15, and movable contact 18'. With switch 18 in the position shown, current from the fixed A.C. voltage source 19 across the secondary Winding 21 of transformer 17 flows through the series resistors 16 and 15, through the switch 18, through the web portion 22 between the detector roll 11 and the metal squeeze roll 9, and returns to the secondary Winding 21 of transformer 17.

The conductivity of the Web portion 22 subjected to current flow is a function of both the amount of liquid added and the conductivity characteristic of the liquid.

The A.C. voltage developed across variable resistor 15 and current limiting resistor 16 is then a function of the amount of liquid on the web and the conductivity characteristics of the liquid.

A representative portion of the voltage developed across resistors 15 and 16 is selected by the potentiometer 23 and is applied through the coupling capacitor 24 to a conventional A.C. voltage amplifier consisting of grid resistor 25, vacuum tube 26, cathode resistor 27, cathode by-pass capacitor 28, audio output transformer 29, and the DC. power supply 42. The A.C. voltage developed in the output or secondary winding 29 of the transformer 29 is then rectified by diode 30, filtered and dampened by capacitor 31 and is applied to the measuring instrument coil 32.

Referring to FIGURE 3', by way of illustration, but not restricted thereto, the measuring instrument coil 32 may be a circuit element of a conventional electric-to-air transducer in a pneumatic controller 33. The coil current produces a corresponding and proportional change in an orifice opening, which regulates the air pressure from a constant air source 34 to be applied to a conventional pneumatic recording instrument 35, and for control purposes, to diaphragm pneumatic motors 36, 37 of a conventional pneumatically loaded squeeze roll set 8 and 9, the pressure of which is air controlled and is a function of the input electric signal.

The upper roll 8 of the squeeze roll set is movable vertically relative to the bottom roll 9 by means of the diaphragm pneumatic motor 36, 37.

The pneumatic controller 33 may be an instrument combining a controller and recorder in one unit, such as Taylor Instrument Companys pneumatic recording controller Type No. 122 R F 137. In the device a known air signal is applied and is called a set point. The unknown signal from an electric-to-air transducer then causes the output pressure applied to the pneumatic actuators 36 and 37 to vary the squeeze roll pressure in the correction direction until the unknown air signal is equal to the set point signal.

The A.C. conductivity measurement of the wet Web 10 is dependent upon both the amount of liquid added and the conductivity characteristics of the liquid 4. It is necessary to take into account the conductivity characteristics of the liquid, since this is subject to variation from time to time.

Liquid conductivity is related to the total ion content. The acidity or alkalinity of a liquid is commonly expressed in terms of pH, a number which is equal to the logarithm of the reciprocal of the positive hydrogen ion content. pH alone is, therefore, not related to A.C. conductivity through a liquid. Total conductivity is related to both the positive hydrogen ion content and the negative hydroxide ion content. Certain salts, for instance, when added to liquids may affect pH to negligible extents while total ion content and total conductivity may be appreciably affected.

The relationship between the conductivity between probes 38, 39, FIGURE 1, immersed in sizing liquid 4 and the conductivity through a hygroscopic Web of textile fibers 22 between metallic detector elements or rolls was determined by experiment. It was determined that for each amount of liquid added to the web, the ratio of liquid conductivity to wet web conductivity is constant, each, of course, being dependent upon constant temperature.

The method, therefore, employed in the measuring apparatus to eliminate the effect of pH, salts, and any other factors which affect conductivity, so as to establish an exact relationship with total liquid pickup only, includes the use of a set of immersion probes in the liquid bath. Selector switch 18 is employed for the purpose of measuring the liquid conductivity between the probes 3 8 and 39 in the same manner as between the detector roll 11 and the squeeze roll 9.

When the operate-standardize selector switch movable contact 18' is moved to engage contact 18a, probes 38 and 39 are then in series circuit with the secondary winding 21 of the transformer 17, and with resistors 15 and 16. The A.C. voltage appearing across resistors 15 and 16 is therefore a function of the conductivity of the liquid bridging the probes 38 and 39.

The constant ratio is, of course, dependent upon the physical spacing and exposure dimensions of both the immersion probes 38, 39 and the detector roll 11 and squeeze roll 9. For an experimental installation, the ratio was determined to be 17:1, the liquid conductivity being 17 times the wet web conductivity.

Once the ratio has been determined for a given installation and the indicating and recording instrument calibrated to read in percent total wet pickup or percent solids pickup, any changes in pH, salt content, or other influencing factors in the liquid bath, can be measured and the instrument recalibrated to eliminate the effect of the aforesaid changes.

Variable resistor 15 is calibrated in units of conductivity and is used to set the instrument to read the wet web conductivity correctly, taking into account the liquid conductivity.

A.-C.- conductivity is employed instead of D.-C. conductivity in order to avoid the effects of polarization of the immersion probes. D.-C. measurements can be used on the web, since the detectors are in constant motion.

The setting of the variable resistor 15 can be made by calculation, using the ratio determined, or it can, by various means, not shown, be set automatically. Such an automatic standarization means could be accomplished by the use of a control motor linked to a balancing potentiometer or an amplifier stage could be incorporated in such a manner that it will present an impedance in one, circuit in constant ratio with another.

The variable resistor 23 is used as a factor to account for the known percent solids in the liquid so that the chart or meter scale of recorder 35 can be calibrated directly in terms of percent solids added to the web.

Referring now to FIGURE 2, I have shown one preferred means for automatically correcting the measurement of the conductivity of the liquid treated web 22 between detector roll 11 and squeeze roll 9 to compensate for variations in the conductivity of the liquid.

The description previously given, which applies to FIG- URE 1, is the same for FIGURE 2, except that two additional ganged switch sections 40 and 41 having movable contacts 40' and 41' respectively, standardize contacts 40a and 4111 respectively, and operate contacts 40b and 41b respectively are added to the operate-standardize switch 18 already described. These additional switch sections merely permit the immersion probes 38 and 39 to be connected to an automatic standardization circuit 44 when the ganged switch is in the operate position as shown.

When the movable contacts 18', 40 and 41 are engaged respectively with the standardize contacts 18a, 40a, 41a, the standardize circuit is the same as that described for FIGURE 1 except for the addition of the switch sections 40 and 41. The apparatus shown in FIGURE 2 is preset prior to operation of the measuring and automatic standardizing means subsequently to be described by adjusting the resistor to correct for conductivity of liquid 4 in the same way as has been described with respect to the apparatus shown in FIGURE 1. Any variation in the conductivity of the sizing liquid 4 after resistor 15 has been preset will be corrected by the automatic standardizing circuit 44.

The conductivity measuring circuit 43 and the automatic standardizing circuit 44 are closed when the movable switch contacts 18, 40', 41' engage contacts 18b, 40b, 41b in the operate position.

The conductivity measuring circuit in the operate position of switch 18 is exactly the same as shown in FIG URE 1 and includes in series circuit contact 1812, the detector roll 11 the length of liquid moistened web or yarn 22 between roll 11 and roll 9, the grounded metal squeeze roll 9, the secondary 21 of the transformer 17, resistor 16, variable resistor 15 and movable contact 18.

The object of standardization of the wet fabric or warp conductivity against the liquid wetting agent conductivity is, as previously explained, to maintain a constant ratio of one conductivity level to the other. Once the instrument is calibrated to record percent wet pickup or percent sizing correctly on the basis of the correlation between the amount of liquid on the web and its electrical conductivity, any changes in the liquid conductivity will, of course, require a compensating change to be made in the setting of the variable resistor 15. In this way, changes in the conductivity of the wetting agent will not be erroneously recorded as changes in the amount of liquid applied to the web.

The automatic means of standardization shown in FIG- URE 2 provides for making a direct change in the current in the coil 32 which actuates the recording instrument in a magnitude which corresponds exactly with that which would otherwise be made in the setting of the variable resistor 15. In this way, the setting of the variable resistor 15 is not automatically controlled and is left in its preset position.

With the switch 18 and ganged sections 40 and 41 in the operate position as shown, the A.-C. voltage developed across variable resistor 15 and current limiting resistor 16 is amplified by vacuum tube 26 and applied to the recorder 35 through coil 32 as a function of both the amount of liquid on the web and the conductivity of the liquid. The elTect of variations in the conductivity of the liquid is then eliminated by applying an opposing current through the coil 32 as a direct function of the liquid conductivity alone.

6. This is accomplished by connecting the immersion probes 38 and 39 in a voltage divider combination consisting also of an adjustable resistance 45 and series-connected, current limiting resistor 46. Voltage is supplied to the dividerfrom the secondary winding 47" of transformer 47. Voltage is supplied to the primary 47 of transformer 47 from A.-C. voltage source 48. At the time of initial calibration, the total resistance of the adjustable resistor 45 and current limiting resistor 46 is set to a value which is equal to the resistance between the probes 39 and 38. Under this condition, the A.-C. voltage developed across the probes 38 and 39 will cause current to flow through the diode 49 and resistor 50.

Since the resistance value of resistor 51 is the same as that of resistor 50 and since equal values of A.-C. voltage are applied through corresponding diodes 49 and 52, the resulting D.-C. voltages developed across resistors 50 and 51 will be equal and their common terminals 53, 53 will be negative with respect to their opposite terminals 55, 56. Capacitors 57 and 58 are provided for smoothing the voltage developed across resistors 50 and 51 respectively.

As the conductivity of the liquid changes, the voltages developed across resistors 50 and 51 will change so that a net diiference voltage will be applied in series with the coil 32. Depending upon the polarity of the difference voltage, the coil current will be made to increase or decrease.

It can be seen that an increase in liquid conductivity will cause a decrease in A.-C. voltage across the probes 38 and 39 and an increase in the A.-C. voltage developed across the series combination consisting of the adjustable resistor 45 and current limiting resistor 46. The rectified D.-C. voltage developed across resistor 50 will then be lower than that developed across resistor 51. Summation of the series D.-C. voltage sources applied to the coil 32 consists of the voltage across capacitor 31, which is a function of web conductivity, an opposing voltage developed across resistor 51, and an aiding voltage developed across resistor 50. Since the opposing voltage developed across resistor 51 is greater than the aiding voltage developed across resistor 50, the current through the coil 32 will be decreased.

Conversely, a decrease in liquid conductivity will result in an increase in the aiding voltage developed across resistor 50 and a decrease in the opposing voltage developed across resistor 51, thus resulting in an increase in current through the coil 32.

In FIGURE 4 there is disclosed a motorized control valve 70 and control circuit effective to regulate the angular position of an existing hand control valve in the air line 71 to the pneumatic diaphragm actuators 36 and 37. This apparatus takes the place of the pneumatic controller device 33 shown in FIGURE 3 and may be used when it is desirable to'convert a hand controlled air supply system for supplying pneumatic diaphragm actuators 36 and 37 to a motor controlled air supply system.

The device shown in FIGURE 4 utilizes a photoelectric meter relay 72 to sense a departure from the desired level of wet pickup. The photocells 73, 74 actuate relays 75, 76 to cause a control motor 77 to either increase or decrease the valve opening 78 depending upon whether the pickup has increased or decreased from the desired value.

Referring to FIGURE 4, a D.-C. voltage from the output coil 32 (see FIGURES 1 and 2), already described, is applied across potentiometer 79. A portion of this voltage is applied to the moving coil 80 of a three-position photoelectric meter relay 72. The meter relay 72 consists of two light sources 81, light shading pointer 82 mechanically attached to the moving coil 80 and two closely spaced photoelectric cells 73 and 74.

The potentiometer 79 is calibrated in terms of Percent Size or Percent Wet Pickup corresponding to the value of voltage from the output coil 32 which will cause the D.-C. voltage selected by the potentiometer 79 to be such that the light shading pointer 82 of the photoelectric meter relay 72 will be positioned precisely between the light beams illuminating the two photoelectric cells 73 and 74.

When the measured pickup increases from the desired value set on the potentiometer 79, the light shading pointer 82 will move upward and shade the light from the upper photoelectric cell 74. Similarly, when the measured pickup decreases from the desired value set on the potentiometer 79, the light shading pointer will move downward and shade the light from the lower photoelectric cell 73. Mechanical stops (not shown) are employed so the pointer 82 cannot travel beyond the completely shaded positions of each photoelectric cell.

The photoelectric cell 73 is connected in series with resistor 83 across the A.-C. line 85. Similarly, photoelectric cell 74 and resistor 84 in series are connected across A.-C. line 85.

The voltage developed across the photoelectric tube 73 is applied from the control grid 87 to the cathode 88 of a gas control tube 86. Similarly, the voltage developed across the photoelectric tube 74 is applied from the control grid 91 to the cathode 92 of gas control tube 90. The cathode 88 and anode 89 of gas control tube 86, and the cathode 92 and anode 93 of the gas control tube 90 are connected respectively in series with coil 75' of plate relay 75 and coil 76' of plate relay 76 across the A.C. line 85.

When the cell 73 is illuminated, its resistance is low, and the A.-C. voltage developed across it is low. When the cell 73 is shaded, as would be caused by a decrease in wet pickup, the cell resistance is high, and the A.-C. voltage developed across it is high.

Since the A.-C. voltage developed across the photoelectric cell 73 is applied from the control grid 87 to the cathode 88 of gas control tube 86, the tube 86 will conduct when its grid 87 and anode 89 are positive with respect to its cathode 88.

Since plate relay 75 is connected in the anode circuit of the gas control tube 86, it is energized by a decrease in wet pickup below the value set on the potentiometer 79. The energization current is pulsating D.-C. rectified and passed by the tube 86.

As described, when the upper photoelectric cell 74 is shaded, as caused by an increase in wet pickup, the grid to cathode voltage applied to the second gas control tube 90 is increased sufiiciently to cause conduction in its anode circuit through plate relay 76.

Similar resistor-capacitor networks comprising resistor 94 and capacitor 95 in series, and resistor 96 and capacitor 97 in series are connected across the plate relay coils 75 and 76, respectively, for the purpose of providing' filtering of the pulsating D.-C. current.

When the wet pickup is equal to the value set on the potentiometer 79, the low-pickup relay 75 and the highpickup relay 76 are both de-energized. When the Wet pickup is low, the low-pickup relay 75 is energized and the high-pickup relay 76 is de-energized. When the wet pickup is high, the high-pickup relay 76 is energized and the low-pickup relay 75 is de-energized.

The upper set of contacts 75a, 76a associated with relays 75 and 76, respectively, serves to operate signal lights 98, 99 to show when the control is measuring a deviation from the preset value set on potentiometer 79 and in which direction the control is acting to correct it. Ordinary neon indicator lamps 98 and 99 are employed with current limiting resistors 100 and 101.

The lower sets of contacts 75b, 76b associated With relays 75 and 76 respectively, close the control motor 77 circuit from common 102 to increase or decrease, depending upon the direction of deviation in wet pickup. When the pickup is determined to be low with respect to set point on the potentiometer 79, the control motor 77, through mechanical linkages 103 reduces the valve opening 78 so as to apply less pressure to the squeeze or pad roll actuators 36, 37. Similarly, when the pickup is high, the control motor 77 increases the valve opening 78 so as to apply greater pressure to the roll actuators and thereby reduce the pickup.

While, in the foregoing description, there have been described and shown the preferred embodiments of the invention, various modifications may become apparent to those skilled in the art towhich the invention rel-ates. Accordingly, it is not desired to limit the invention to this disclosure and various modifications and equivalents may be resorted to, falling within the spirit and scope of the invention as claimed.

I claim:

1. In a textile machine having means feeding a strip of connected textile fibers therethrough, means imparting liquid size to the strip of connected textile fibers, means varying the amount of liquid size retained by the strip, and means receiving the size treated strip; the improvement comprising electrical conductivity measuring means including a pair of spaced detector electrodes contacting said size treated textile strip and connected in circuit with an electric voltage source to pass an electric current through the size treated textile strip intervening said detector electrodes for measuring the electrical conductivity of the size treated strip of connected textile fibers, electrical conductivity measuring means for measuring the electrical conductivity of said liquid size, means correcting the electrical conductivity measurement of said size treated strip of connected textile fibers for variations in electrical conductivity of the liquid size, means utilizing the corrected electrical conductivity measurement of said size treated strip of connected textile fibers for controlling the means varying the amount of liquid size retained by said strip of connected textile fibers.

2. Measuring apparatus for determining the amount of size retained in a strip of connected textile fibers being treated in a textile machine having means feeding a strip of connected textile fibers therethrough; said apparatus comprising means imparting liquid size to the strip of connected textile fibers, and means receiving said strip after liquid size is imparted thereto, said measuring apparatus including electrical conductivity measuring means including a pair of spaced detector electrodes contacting said size treated textile strip and connected in circuit with an electric voltage source to pass an electric current through the size treated textile strip intervening said detector electrodes for measuring the electrical conductivity of the size treated strip of connected textile fibers, electrical conductivity measuring means for measuring the electrical conductivity of said liquid size, means for applying a correction factor to said electrical conductivity measurement of said size treated strip of connected textile fibers to account for the electrical conductivity of the liquid size, and means responsive to the corrected measurement of the electrical conductivity of said treated strip of connected textile fibers for indicating the amount of size retained in said size treated strip, the amount of size retained being in a direct function of said corrected electrical conductivity measurement.

3. A sizing machine for strips of textiles or the like having squeeze rolls for varying the amount of size retained on the textile strips, comprising in combination pneumatic actuators for controlling the pressure applied by said squeeze rolls on said textile strips, valve means for controlling the pneumatic pressure applied to said actuators, and an electric control motor for controlling said valve means, electric measuring means including a pair of spaced detector electrodes contacting said size treated textile strip and connected in circuit with an electric voltage source to pass an electric current through the size treated textile strip intervening said detector electrodes for producing an electric voltage signal proportional to the amount of size retained on said textile strip, control means for said electric control motor including a three position photoelectric meter relay connected to said electric measuring means, the three positions of said meter relay corresponding respectively to a predetermined low quantity of retained size, a predetermined correct quantity of retained size and a predetermined high quantity of retained size, an increase circuit for said control motor for energizing said control motor in a direction to actuate said valve to decrease the pneumatic pressure applied to said pneumatic actuators, and a decrease circuit'for said control motor for energizing said control motor in a direction to actuate said valve to decrease the pneumatic pressure applied to said pneumatic actuators, means responsive to said low quantity position of said photoelectric meter relay for energizing said decrease circuit, and means responsive to said high quantity position of said photoelectric meter relay for energizing said increase circuit, said motor being de-energized when said photoelectric meter relay is in the correct quantity position.

4. A Web coating machine measuring apparatus for determining the amount of liquid coating material retained on the liquid coated web, comprising in combination electrical conductivity measuring means including a pair of spaced detector electrodes contacting said liquid coated web and connected in circuit with an electric voltage source to pass an electric current through the liquid coated web for measuring the electrical conductivity of the liquid coated web, electrical conductivity measuring means for measuring the electrical conductivity of said liquid coating material, means for applying a correction factor to said electrical conductivity measurement of said liquid coated web to account for the electrical conductivity of the liquid coating material, and means responsive to the corrected measurement of the electrical conductivity of said liquid coated web for indicating the amount of coating material retained on said web.

5. The apparatus as set forth in claim 4 wherein said means for applying a correction factor to said electrical conductivity measurement of said liquid coated web to account for the electrical conductivity of the liquid coating material is automatic.

6. A sizing machine for strips of textiles or the like, having means for varying the amount of size retained on the textile strips, comprising in combination fluid motors for controlling the means for varying the amount of size retained on the textile strips, valve means for controlling the fluid applied to said fluid motors and an electric control motor for controlling said valve means, electric measuring means including a pair of spaced detector electrodes contacting said size treated textile strip and connected in circuit with an electric voltage source to pass an electric current through the size treated textile strip intervening said detector electrodes for producing an electric voltage signal proportional to the amount of size retained on said textile strip, control means for said electric control motor including a three position photoelectric meter relay connected to said electric measuring means, the three positions of said meter relay corresponding respectively to a predetermined low quantity of retained size, a predetermined correct quantity of retained size and a predetermined high quantity of retained size, an increase circuit for said control motor for energizing said control motor in a direction to actuate said valve to increase the fluid pressure applied to said fluid actuators, and a decrease circuit for said control motor for energizing said control motor in a direction to actuate said valve to decrease the fluid pressure applied to said fluid actuators, means responsive to said low quantity position of said photoelectric meter relay for energizing said decrease circuit, and means responsive to said high quantity position of said photoelectric meter relay for energizing said increase circuit, said motor being de-energized when said photoelectric meter relay is in the correct quantity position.

References Cited by the Examiner UNITED STATES PATENTS 2,215,805 9/40 Wills 324 2,263,017 11/41 Sparrow 32465 2,558,392 6/51 Seney 32465 XR 2,615,822 10/52 Huebner 1l747 2,703,386 3/55 Seney 32465 2,942,352 6/60 Eicken-Estienne 32465 XR 2,956,905 10/60 Jones et al. 118-9 2,977,925 4/61 Norton 1l766 XR WILLIAM D. MARTIN, Primary Examiner.

RICHARD D. NEVIUS, Examiner.

Claims (1)

1. IN A TEXTILE MACHINE HAVING MEANS FEEDING A STRIP OF CONNECTED TEXTILE FIBERS THERETHROUGH, MEANS IMPARTING LIQUID SIZE TO THE STRIP OF CONNECTED TEXTILE FIBERS, MEANS VARYING THE AMOUNT OF LIQUID SIZE RETAINED BY THE STRIP, AND MEANS RECEIVING THE SIZE TREATED STRIP; THE IMPROVEMENT COMPRISING ELECTRICAL CONDUCTIVITY MEASURING MEANS INCLUDING A PAIR OF SPACED DETECTOR ELECTRODES CONTACTING SAID SIZE TREATED TEXTILE STRIP AND CONNECTED IN CIRCUIT WITH AN ELECTRIC VOLTAGE SOURCE TO PASS AN ELECTRIC CURRENT THROUGH THE SIZE TREATED TEXTILE STRIP INTERVENING SAID DETECTOR ELECTRODES FOR MEASURING THE ELECTRICAL CONDUCTIVITY OF THE SIZE TREATED STRIP OF CONNECTED TEXTILE FIBERS, ELECTRICAL CONDUCTIVITY MEASURING MEANS FOR MEASURING THE ELECTRICAL CONDUCTIVITY OF SAID LIQUID SIZE, MEANS CORRECTING THE ELECTRICAL CONDUCTIVITY MEASUREMENT OF SAID SIZE TREATED STRIP OF CONNECTED TEXTILE FIBERS FOR VARIATIONS IN ELECTRICAL CONDUCTIVITY OF THE LIQUID SIZE, MEANS UTILIZING THE CORRECTED ELECTRICAL CONDUCTIVITY MEASUREMENT OF SAID SIZE TREATED STRIP OF CONNECTED TEXTILE FIBERS FOR CONTROLLING THE MEANS VARYING THE AMOUNT OF LIQUID SIZE RETAINED BY SAID STRIP OF CONNECTED TEXTILE FIBERS.

Images