GB2208010A - Device for measuring liquid consumption of coating apparatus - Google Patents

Description

i- 1 2 U 6.1 0 10 Device for measuring the liquor consumption of an

application unit The invention relates to a device for measuring the liquor consumption of an application unit2 for example a sizing installation, a padding mangle or the like. having a main trough receiving the liquor, having an application means provided on the main trough for the application of the liquor to a sub-stratum, especially to a band of threads, and having an overflow from the main trough to the reservoir, with a pump connected into a return conduit between reservoir and main trough and with means for measuring the liquor level in the reservoir.

In the application or applicator part with the squeezer rolls of a sizing device or a padding mangle it is general to work with constant liquor content. The liquor level in the main trough used for the actual sizing is kept constant by an overflow. At the same time liquor is constantly conveyed out of a reservoir into the main trough. The liquor runs over the overflow partly back into the reservoir, and partly it is conveyed away by the sub-stratum to be wetted or impregnated, for example a band of threads or a textile cloth web. Since the liquor level in the main container is kept constant by.its overflow, the liquor absorption of the sub-stratum reduces the liquor level in the reservoir. This variation of level is used as measured value for the liquor consumption, that is for the liquor absorption of the through-passing sub-stratum.

The speed of variation of the liquor level in the reservoir depends upon the liquor consumption of the sub- - Z - stratum and the size of the liquid surface area of the reservoir. The liquor consumption by the sub-stratum depends upon its speed and absorptivity and also upon the squeezing-out effect and the viscosity of the liquor. Obviously all these influences-can add up to a very large or to a relatively small liquor consumption per unit of time. If for example the liquor consumption is to be ascertained by a level measurement in the reservoir, and in the case of high values of speed of transport, liquor absorption and viscosity a few seconds suffice for the measurement, in working at creeping speed with low liquor absorption ten to fifteen minutes can be necessary for a measurement. In the case of low liquor absorption therefore a substantially lower measured volume must be provided than for a high liquor consumption. Since the reservoir serves as store for the liquor overflowing out of the main trough, a substantial v,ariation of the total volume of the reservoir cannot be effected if the installation is to be of universal usability, that is both for high- and low liquor consumption.

The liquor consumption can also be defined as the liquor quantity which is to be replenished, after the fall of the level in the reservoir from an upper to a lower level, from a liquor preparation system. In general the measurement of the liquor consumption can be limited to the moment of replenishment of the reservoir. If however more frequent intermediate measurements are desired, the differences to be measured - especially in operation-at creeping speed - can lie in the range of measuring accuracy of the measuring means I provided for normal operation. Thus if necessary relatively expensive special methods and means may have to be provided, even when measurements are desired with minimum liquor consumption, for example even in the case of minimal application of liquor to a substratum.

The invention is based upon the problem of so improving and completing the initially stated device for the measuring of the liquor consumption of an application unit that without appreciable additional investment and labour expenditure it is ina position, even in the case of extremely low liquor consumption per unit of time, to deliver a measurement result for the liquor consumption in a short time in each case, f or example within a few seconds, the accuracy of measurement of which corresponds to that in the case of high liquor consumption. The solution according to the invention consists, for the device as initially stated with a main trough, accommodating the liquor to be applied to the sub-stratum, with overflow to a reservoir and with a return conduit between reservoir and main trough with pump connected into it and with means for the measurement of the liquor level in the reservoir, in that a precision-measurement unit for connection at least at creeping speed is set into the overflow between main trough and reservoir. According to the further invention as precisionmeasurement unit there is provided either a measuring vessel arranged within or outside the reservoir, with overflow to the reservoir, or a precision-measurement zone formed as constriction of cross-section of the reservoir.

The invention achieves the object that, without any i variation of the ordinary measuring device and procedure on the reservoir, and without influencing the operation of the machine, an exact measurement even of a minimum liquor consumption is possible at creeping speed with high squeezingout and/or low liquor absorption. The precis ion- measurement unit installed into the overflow between main trough and reservoir or into the reservoir itself is rather practically without influence of any kind upon the operation of the application unit and can in general be set in action constantly, even if a measurement result is not needed at the moment.

According to the foregoing the precis ion-measurement unit in accordance with the inventioncan be formed as a measuring vessel arranged within or outside the reservoir. Such a measuring vessel can be filled from the overflow of the main trough and in turn possess an overflow to the measuring vessel. According to desire then a measurement of the liquor consumption can be effected either in the measuring vessel or in the reservoir. The measuring vessel can preferably (together with a connecting conduit to the pump delivering by way of a return conduit from the reservoir into the main trough) constitute a by-pass for the liquor path leading by way of the reservoir. Above all in this case the conduits between reservoir and measuring vessel for the one part and pump for the other part can contain a valve each, only the one or the other of the valves having to be opened in each case, in such a way that the path from the overflow of the main vessel to the pump leads either (in the normal case) only by way of the 1 - reservoir or (at creeping speed, minimum application, etc.) only by way of the measuring vessel.

If as precision-measurement unit according to the invention a precisionmeasurement zone formed as crosssectional constriction of the reservoir is provided, a tube part of bottle-type thinness, a connector pipe or the like can be integrated into the reservoir. Instead it is also possible to provide within the reservoir a height section defined by a displacement body for securing within the reservoir.

In general the precision-measurement zone will be arranged in the upper part of the reservoir. In the case of low liquor consumption a consumption measurement can be demanded immediately if at first so much liquor is admitted from a liquor reserve into the reservoir that the liquor level passes into the precision-measurement zone. The time duration of the fall from the replenishment level to a level establishing itself after the elapse of a specific time produces the liquor consumption per unit of time.

Details of the invention will be explained by reference to the diagrammatic drawing of examples of embodiment, FIGURE 1 shows a device for measuring the liquor consumption with measuring vessel built into the reservoir; FIGURE 2 shows a device corresponding to Figure 1 with measuring vessel arranged outside the reservoir with overflow to the reservoir; FIGURE 3 shows a precision-measurement unit for the measurement of the liquor consumption with filler connector of bottleneck-type narrowness provided on the top of the wherein: - reservoir; and FIGURE 4 shows a precision-measurement unit with displace -ment body arranged f ixedly in the upper level region of the reservoir.

The device according to Figures 1 and 2 consists of a main trough 2 receiving the liquor 1, with plunger roll 3 arranged therein and with a squeezer roll pair 4. The sub-stratum 5 to be treated in each case, which may be a band of threads or a textile clotn web, in operation runs in the direction of the arrow 6 about the plunger roll 3 through the liquor 1 and is squeezed out in the squeezing mechanism 4 to the degree of wetting desi--ed in each case. In order to keep the amount of blocking of --he sub-stratum 5 with liquor 1 constant at the entry of the squeezer roll pair 4, the level 7 of the liquor 1 in the main trough 2 is adjusted to constancy by an overflow 8.

From the main trough 2 the liquor 1 passes by way of the overflow 8 and a channel 9, preferably through a cleaning sieve 10, into a measuring vessel 11, which is arranged, in the example of er7bodiment according to Figure 1 within and in the example of embodiment according to Figure 2 outside a reservoir 12 provided as liquor reserve. From the measuring vessel 11 into the reservoir 12 the liquor again passes by way of an overflow 13. Both the measuring vessel 11 and the reservoir 12 possess conveying conduits 14 and 15 connected to the respective vessel bottoms, which conduits lead by way of a valve 16 and 17 each to a pump 18 with conveying conduit 19 to the main trough 2. Finally the supply conduit 20 with valve 21 of a reservoir 22 accommodating reserve liquor from a liquor 1 1.

ii 1 preparation system is allocated to the measuring vessel 11 or the reservoir 12.

If with the device according to Figure 1 or 2 a substratum of high liquor absorptivity is to be treated at high working speed, possibly at high liquor viscosity, the measurement of the liquor consumption is effected in the usual way by ascertaining of the drop of the liquor level 23 in the reservoir 12 by an amount H per unit of time. For this measurement it is possible to-determine the quantity of liquor which is needed after a specific working time from the reservoir 22 to reach the liquor level 23 again.

If however the sub-stratum 5 is drawn at creeping rate through the liquor 1 and the squeezer roll pair 4 and/or if the liquor possesses a very low liquor-absorption capacity, the liquor consumed per unit of time can be so low that sufficient time does not remain for the described measurement in the reservoir 12.

While otherwise the liquor 1 flowing from the overflow 8 of the main trough 2 to the reservoir 12 is conveyed by way of the bottom valve 17 and the conduit 15 of the reservoir 12 to the pump 18 and by way of a conveying conduit 19 back to the main trough, in accordance with the invention it is provided to insert a measuring vessel 11 with bottom valve 16 as by-pa ss to the reservoir 12. When the bottom valve 16 of the measuring vessel 11 is opened the bottom valve 17 of the reservoir 12 is expediently closed, so that the whole of the liquor arriving by way of the channel 9 is sucked through the measuring vessel 11 and its bottom valve 16 to the pump 18.

According to definition the cross-section, corresponding to the liquor level, of the measuring vessel 11 is small compared with the corresponding cross-section of the reservoir 12. A ratio of the order of size of 1: 10 has here proved itself expedient both in the example of emb"%odiment according to Figure 1 and in that according to Figure 2.

If the measurement of the liquor consumption is to be executed in the measuring vessel 11 it is possible - in principle just as in the reservoir 12 - to measure the time in which the liquid level 24 of the measuring vessel 11 falls by the amount h. For the measurement of the variation of level per unit of time the usual measurement methods can be used, for example a pressure cell or a level detector 25.

In the examples of embodiment according to Figures 3 and 4 the application unit consisting of the main trough 2 and -the rolls 3 and 4 possesses substantially the same construction as in Figures 1 and 2. The liquor level 7 in the main trough 2 is kept constant by a liquor return by way of a conduit 19 with pump 18 from a reservoir 12 in combination with an overflow 8. From the overflow 8 excess liquor passes in the direction of the arrow 26 into the reservoir 12.

The reservoir according to Figure 3, designated as a whole by 12, possesses a thick-bodied under part 27 with a crosssection which readily renders possible the measurement H, as described with reference to Figures 1 and 2, in the reservoir 12, even at maximum liquor consumption. At the head of the reservoir 12 according to Figure 3 there is a precisionmeasurement zone formed as connector piece 28, in which the surface area available for the liquor is small compared with the corresponding cross-section of the under part 27. Thus if in the main trough 2 the liquor consumption per unit of time is very small, the liquor consumption per unit of time will be measured not, as in normal operation, in the region H of the under part 27, but in the region h of the connector piece 28.

Figure 4 shows an example of embodiment resembling Figure 3, but in which it is not a constriction of the reservoir designated as a whole by 12 which is provided but a displacement body 30 is fixedly arranged within the reservoir. While a measurement in the lower region 31 of the reservoir 12 beneath the displacement body 30 can be carried out in the usual way, somewhat as in the lower part 27 of the reservoir 12 in Figure 3, on the circumference of the displacement body 30, on account of the small cross-section remaining for the liquor, even at low liquor consumption, a relatively rapid change of level per unit time occurs, which can be measured correspondingly easily and quickly.

A precise measurement of the liquor level either in the normal region or equally in the precision-measurement part can take place in all examples of embodiment with the aid of one or more pressure cells or level detectors 25.

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Claims (7)

1. Claims l.) Device for the measurement of the liquor consumption of an

   application unit, for example a sizing installation, a padding mangle or the like, having a main trough (2) accommodating the liquor (1), having an application means (3 4) provided on the main trough (2) for applying the liquor (1) to a sub-stratum (5), especially to a band of threads, and having an overflow (8) from the main trough (2) to a reservoir (12), having a pump (18) connected-into a return conduit (19) between reservoir (11) and main trough (2) and having means for measuring the liquor level. (23) in the reservoir (11)g characterised in that into the overflow (11) between main trough (2) and reservoir (12) there is set a precisionmeasurement unit (11) for setting in action at least when the application unit is at creeping rate.
2. 2.) Device according to Claim 1, characterised in that as precis ionmeasurement unit there is provided a measurement vessel (11) arranged within or outside the reservoir (12)5 with overflow (13) to the reservoir (12).
3. 3.) Device according to Claim 2, characterised in that the measurement vessel (12) together with a connecting conduit (14) to the pump (18) constitutes a by-pass short-circuiting the liquor path (15) leading by way of the reservoir (12).
4. 4.) Device according to Claim 3, characterised in that the conduits (14, 15) between measurement vessel (11) and reservoir (12) for the one part and pump (18) for the other part each contain a valve (16), only the one or the other valve having to be opened.
5. 5.) Device according to Claim 1 characterised in that as precis ionme asurement unit there is provided a precisionmeasurement zone (28, 30) formed as constriction of crosssection of the reservoir (12).
6. 6.) Device according to Claim 5, characterised in that a connector piece (28) of bottle-type thinness of the reservoir (12) is provided as precision-measurement zone.
7. 7.) Device according to Claim 5, -characterised in t hat a height section, defined by a displacement body (30), within the reservoir (12) is provided as precision-measurement zone.

   S.) Devi-...e for the measurement of the liquor consumption of a liquor application unit, substantially as described with reference to Figure 1,2, 3 or 4 of the accompanying dtawings.

   Published 1988 at The Patent Office State House. 66 71 High Holborn, London W01Ft 4TP. F'urther copies may be obtained from The Patent Office,. Sales Branch, St Mary C: ay, Orpington, Kent BR5 3RD. Printed by Multiplex techniques ltd, St Mary Cray, Kent, Con. 1187.