CN100439582C - Control method and system for weft braking mechanism capable of regulating mechanical tension of yarn in loom automatically - Google Patents

Abstract

An improved method for controlling electrically operated weft-braking devices, capable of automatically adjusting the mechanical tension of the weft yarn (F) in mechanical-picking weaving machines (TE), is disclosed herein. The excitation current (Ie) of the weft-braking device (LF) is controlled by an adjustment loop (A) using a signal (tens-mis), which is a measure of the actual tension of the yarn, as a feedback signal for the adjustment loop (A). The improvement comprises employing an average value (TMx), which is computed at predetermined intervals (x) of weft picking and for a predetermined number (i) of picking strokes, in order to measure the direct tension of the thread (F), so that said average value (TMx) is substantially stable and not affected by fluctuations due to variations of the parameters of the weaving process.

Description

Automatically be adjusted in the control method of the weft yarn braking equipment of yarn mechanical tension in the weaving loom

(1) technical field

The present invention relates to control method and the system that the electronic operation fabric braking equipment of yarn mechanical tension in the mechanical weaving loom of throwing a spear is used in automatic adjusting.

More particularly, invention relates to the system of mechanical tension that automatic adjusting is supplied to the yarn of weaving loom, is clamped weft yarn and it is introduced shed open by mechanical device therein.Such machine comprises Rapier looms and gripper shuttle loom and other, and fluid jet loom is outside invention field.

(2) background technology

Well-known with regard to fabrication processes, weft yarn from spool by be equipped with manual adjustment inlet braking equipment, the weft yarn supply by at least one electronic operation weft yarn braking equipment is supplied to loom then, two braking equipments are placed between spool and the loom.

Automatic regulating system has originally developed into control electronic operation weft yarn braking equipment, to finish following target:

-fully the mechanical tension of maintenance yarn is that constant does not rely on during weaving: change from the full empty geometry that it is set that is set to during a) spool is advanced, b) be the difference setting of the inlet braking selection of described weft yarn supply, c) different angles of weft yarn, d) wearing and tearing of braking element in the path between spool and loom;

-guarantee in weft yarn is throwed a spear process specific instantaneous during, normally during the step of folder, during weft yarn is sent to the step of drawing yarn gripper from fixing yarn gripper and during the arrival step of yarn, the mechanical tension of weft yarn has sufficient intensity.

-guarantee whole draw the yarn process during, yarn mechanical tension value does not reach excessive level, if surpassed, can cause yarn to disconnect on the more weak point of yarn.

For relying on the following regulating loop of will disclosed use measuring the signal of yarn actual tension, the above-mentioned automatic regulating system of this purpose acts on the Electronic Control of weft yarn braking equipment, this signal is produced by measuring transducer and as the feedback signal in loop, its reference is the prearranged signals corresponding to yarn expectation tension force.Signal from behind deduct the front to obtain error signal, then by logic device (PID logic of class piece) process errors signal to obtain corrected signal so that it can remove error.Corrected signal will make weft brake be applied to the braking action of ratio intensity by the power circuit that is fit to.Described corrected signal is also referred to as " braking action " in the following description.

Yet, clearly illustrate that corresponding to signature tune line chart (in Fig. 3, drawing) the described signal that is obtained by the weft yarn of described known regulating loop braking by control is subjected to the fluctuation that continues with high-frequency with fine rule as the weft yarn actual tension of weaving loom (being) main shaft angle position (unit is degree) function by comprising the weft yarn supply and the assembly feed of the weft yarn braking of overlapping plates being arranged.

Such fluctuation is the variation effect instability that produce and that make regulating loop by the above-mentioned parameter of mentioning of fabrication processes (path of the geometry of spool, the wearing and tearing of braking element, yarn or the like).Therefore, do not reach the accurate control of yarn tension and the normal operation of fabrication processes, because they are subjected to from the stroke of throwing a spear to the Next variation that can't predict yet.

(3) summary of the invention

The present invention is at removing such shortcoming.

Especially, the main purpose of the present invention is improve to measure the method for the actual machine tension force of weft yarn and weft yarn control system, for fear of the described rapid fluctuations of tension signal and prevent to control the regulating loop thing followed fluctuation of service of the exciting current of weft yarn braking equipment.

By being arranged, the method and system of listing in the feature in the appended claim finishes this target according to the present invention.

For the direct tension force (it produces the feedback signal of weft yarn braking regulating loop) of measuring yarn, the present invention is fully according to the notion of the instantaneous value that uses mean value rather than tension force, described mean value is the scheduled time slot of throwing a spear at weft yarn and the stroke of throwing a spear of predetermined quantity is calculated, so that the fully stable influence that is not subjected to described rapid fluctuations of whole process.

Therefore, the method for invention comprises:

-be subdivided into several intervals to what weft yarn was throwed a spear total time, for instance as the weaving loom main shaft predetermined and the modifiable anglec of rotation be presented,

-be that each such interval is provided with the predetermined reference value (it is modifiable) for the average Yarn braking of described interval expectation,

-between the introductory phase by considering mean value calculation for each all tension force of stroke of throwing a spear corresponding to each mean tension at interval,

-throw a spear the mean value calculation of stroke corresponding to the mean value at consider interval from each i,

-mean value of each predetermined reference value and corresponding measurement is made comparisons, to obtain error signal and corrected signal afterwards, corrected signal is used to produce the brake operating of eliminating error.

(4) description of drawings

From following detailed description and with reference to the accompanying drawings characteristics, purpose and the advantage of the inventive method and system all can show, these all provide by nonrestrictive example.

Fig. 1 is the calcspar that with weft yarn braking regulating loop weft yarn is offered the system of mechanical pick loom according to original technology.

Fig. 2 is similar in appearance to the calcspar of Fig. 1 according to the improved feeding system of the present invention.

Fig. 3 is the curve map that yarn tension that is obtained by Fig. 1 regulating system and the tension force that is obtained by Fig. 2 improvement system are made comparisons, and described tension force is that the function as the weaving loom angle position provides.

(5) specific embodiment

With reference to Fig. 1, SAL is the known system that weft yarn F is supplied to mechanical pick loom TE.Twine above system comprises weft yarn F spool RO, weft yarn supply equipment P, put into the weft brake LF between loader P and the loom TE, for instance in the type that overlapping plates is arranged described in the EP622.485, and the sensor TM that directly measures the mechanical tension T value of yarn F; Described sensor is the downstream that is placed on brake LF.Just itself is known, and loader P comprises cylinder TA, and the cursor BR that is controlled by motor M0 on it twines and recovers a plurality of yarn coils, forms weft yarn deposit RT.With regard to the requirement of loom TE, when each weft yarn is introduced yarn coil, unclamp and pass yarn guide rod GA from cylinder TA.

Similarly, just itself is known, and Yarn Brake LF comprises fixed head and removable plate, between them by yarn and motor actuator MF.The latter is driven by the exciting current that sensor TM produces Signal Regulation, promoting removable plate with either large or small strength facing to fixed head, thus the adjusting braking effect, just braking action AF is applied on the yarn F.

For this purpose, sensor TM produces signal tens-mis, and it represents to control the feedback signal of the loop A of weft brake LF in fact.Such control loop comprises subtract logic piece 1, therein subtraction signal tens-mis from the reference signal tens-rif of expression weft yarn F mechanical tension desired value.Therefore, the output of subtracter 1 is exactly the error signal e rror of expression with reference to the tension force differences of tension force and instantaneous measurement under consideration.

Signal error is applied to the input of known PID adjuster 2, here calculates and revises braking reference signal fren-ref, with erasure signal error.By logical block 3 and power circuit DRV, signal fren-ref produces exciting current I _e, it applies the braking action AF that roughly is directly proportional with described signal fren-ref to brake LF.The loop (comprises one part of current I for instance by the additional feedback signal fren-info that is sent to logical block 3 _e) closed better.

With reference to Fig. 2, wherein similar or corresponding part has same reference number, has described now according to improvement content of the present invention.This improvement comprises and is subdivided into predetermined and modifiable interval x during weft yarn throwed a spear, and for instance as being presented (Fig. 3) in loom TE main axis rotation angle, below describes especially:

70 spend in the 100 degree scopes first at interval, corresponding to the step of folder weft yarn,

Spend to second interval of 160 degree 100 in abutting connection with first, be introduced into the step of shed open by fixing yarn gripper corresponding to weft yarn,

Spend to the 3rd interval of 200 degree 160 in abutting connection with second, corresponding to weft yarn is sent to the step of drawing yarn gripper from fixing yarn gripper,

Spend to the 4th interval of 280 degree 200 in abutting connection with the 3rd, be introduced into the step of shed open by the traction yarn gripper corresponding to weft yarn,

Promptly at interval last 280 the 5th of spending to 320 degree, as to throw a spear corresponding to weft yarn end.

Clearly, introducing time segmentation quantity x and their angle amplitude at interval is unconfined and only is illustrative specific to above value.

In addition, according to the present invention and as shown in Figure 2, also be that each angle intervals x determines braking reference value RFx, wherein x is that n is the quantity (n=5 in the example of this explanation for instance) at segmentation interval 1 in the scope of n.Each reference value forms the desired value that acts on average braking on the yarn F at interval at corresponding x like this.

By according to method of the present invention, calculate throw a spear during corresponding to each mean tension of x at interval, to obtain a cell mean Tmxi, wherein " i " is the quantity of the stroke of throwing a spear considered.Except the mean value (Tmxo) that electric current is introduced, below the machine controller that will further describe is also stored the mean tension value corresponding to last m the stroke of throwing a spear, and wherein m is preferably in 0 to 7 scope.In the example of Fig. 2, m is in 0 to 3 scope, the ongoing stroke of throwing a spear of its intermediate value 0 expression.

For this purpose, comprise instantaneous value tel-pos (it by the angular transducer SA that with axle link to each other provided) the calculated value Tmxi of effective logical block 1 of above-mentioned machine controller according to tension force instantaneous value tens-mis and loom TE main shaft angle position.In addition, at each stroke of throwing a spear, subsequent logic piece 2 calculates corresponding to all mean value TMx corresponding to the mean value of each preceding value Tmxi at interval, and is as follows:

$\mathrm{TMx}=\frac{\underset{i=0}{\overset{n}{\mathrm{\Σ}}}{\mathrm{TMx}}_i}{n+1}$

In addition, logical block 3 is made comparisons the mean value TMx of each braking reference value RFx and corresponding interval x, and, during x, will use braking action AFx (to eliminate error) at whole brake cabin to throw a spear next time with regard to known definite brake LF itself according to the error from this comparative result.Follow this step, as the function of loom TE shaft angle degree position tel-pos, at the output fren-ref logical block 4 conversion value AFx of place.Produce exciting current Im by logical block 5 and power circuit DRV signal AFx, it excites braking driver MF to produce corresponding braking action AFx.

In the curve map of Fig. 3, the curve of drawing with thick line has shown the mechanical tension value, these tension values be in weft yarn, detect and handle by the method for the mean value that on predetermined angle intervals x, calculates according to the present invention and to get, such curve does not have high-frequency fluctuation or variation.

Obviously, can from the content of describing and illustrating by non-limitative example, change implementation detail widely, and not leave scope of invention.

Claims (3)

1. one kind is used for being adjusted in the throw a spear method of tension force of weaving loom (TE) weft yarn (F) of machinery by electronic operation weft yarn braking equipment, the exciting current (Ie) of wherein said weft yarn braking equipment (LF) is controlled by regulating loop (A), regulating loop (A) uses the feedback signal of the measuring-signal (tens-mis) of the true tension force of yarn as regulating loop (A), it is characterized in that this method may further comprise the steps:

On the point in succession that each weft yarn is throwed a spear, measure the tension value of yarn;

For each of described weaving loom stroke of throwing a spear will average at each the yarn tension sample (tens-mis) of a plurality of predetermined space x of this stroke of throwing a spear, to obtain a plurality of tension value Tmxi of each correspondence of throwing a spear;

Average each described tension value Tmxi is as moving average, to obtain time corresponding mean tension value TMx on the throwing a spear in succession of predetermined quantity;

Each time averaging tension value TMx and relatively corresponding to each predetermined reference value RFx of the yarn tension of each expectation at interval, so that generate each error signal AFx; And

For the backfeed loop of controlling described weft yarn braking equipment calculates corrected signal (fren_ref), so that eliminate described error.

2. the method for claim 1 is characterized in that, is subdivided into angle intervals during described weft yarn is throwed a spear, and they provide as weaving loom (TE) main axis rotation angle.

3. by the described method of claim 2, it is characterized in that, be subdivided into during described weft yarn is throwed a spear five intervals (x1...x5) respectively corresponding to: the step, weft yarn of folder weft yarn by fixing yarn gripper be introduced into shed open step, weft yarn be sent to the step, the weft yarn that draw yarn gripper from fixing yarn gripper be introduced into the step of shed open, the final step that weft yarn is throwed a spear by drawing yarn gripper.

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