DE2034526C - Method and device for adjusting the medium flowing through a line to a predetermined flow rate - Google Patents

Description

The fulfillment relates to a procedure for Setting the medium flowing through a line 3b to a predetermined flow rate at which with a large duichfoot the inside diameter the line is reduced while continuously measuring the flow until you see the specified Flow adjusts. Furthermore, the invention deals with a device / for implementation of the procedure.

With the usual flow regulators, the reduction is the inside diameter of the line is usually done by adjusting a valve. Here / 11 reference is made to German patents 856 364 and 827 719, for example.

The known valves for setting the medium flowing through a line to a predetermined one However, flow values cannot be equally successful in all applications can be used. This applies, for example, to those used today that are operated with a constant flow rate Devices for analyzing gaseous.! or liquid samples too. Such analyzers are known, for example, from US Pat. No. 3,241,432. These analyzers work preferably with a very low constant sample flow rate at a high sample analysis speed. It is therefore necessary to have a small sample per analysis and a large number of samples to be made available per time unit. There is an advantage of the low sample flow in that the peristaltic pumps, which are contained in the analyzers and for pumping through the samples consisting of gaseous or liquid media are used, with low operating speeds and be able to work with squeeze tubes with an optimal inner diameter. In the automatic analysis of blood fluid samples, however, difficulties arise when the inner diameter the lines or hoses is smaller than 0.381 mm. There is then namely the Danger that the lines or hoses with solid or semi-solid substances, for example agglutinins, contained in the blood fluid samples smd. clog. For such analyzers you have to use hoses or lines, their Inside diameter is greater than 0.381 mm. On the other hand, however, the inner diameter of the lines should be as small as possible to accommodate the low flow rate of the analyzer. As is well known the flow rate changes proportionally with the square of the inner diameter of the used Lines and hoses. If you now have lines or hoses with a nominal diameter but 0.406 mm is used, thin occurs due to the current manufacturing violations. the problem on. that big changes in the flow uutm.-t.en, since the Inner diameter partly increased. 0.406 mm deviates. Such lines and hoses are therefore useless for constant flow analyzers unless calibration or accurate Adjustment of the flow is carried out.

The invention is thus based on the task flow in a simple way through a loiiung of the gaseous or liquid * medium to set a specified flow rate and a Calibrate the line or hose * with regard to the flow rate.

To solve this problem i, t that described at the beginning Method according to the invention, characterized in that when using an elastic Line / ur reduction of flow. . the line is pulled into you.

In this way it is without the hassle and Space-occupying Zu-.ai/miuel possible, exactly one set the specified flow rate. After the elongated line on the given Flow calibrated L-t, wiiJ in your elongated State left.

An apparatus for carrying out this method is characterized according to the invention, that a fastening device holds the inlet end of the elastic conduit in place so that. '» a movable clamp at the outlet end of the conduit is clamped and that another fastening device is the outlet end of the in the The length of the drawn line is held in place.

The method according to the invention and the device for performing the Process application in hose queue pumps. The elongated line itself can do this Form squeeze tube and progressing in the longitudinal direction corresponding to the direction of flow be squeezed together. The calibrated line can also be connected to another pump or from some other source of constant pressure with a gaseous or liquid! Medium are supplied.

Further advantages and details of the invention are explained with reference to figures.

Fig. 1 and 2 show a longitudinal cross-section durcl a peristaltic pump and are used to explain the method and a device Calibration of the pump hoses according to the invention;

Fig. 3 shows in perspective the hose support frame for the in Figs . illustrated pumps;

Figure 4 is a side view of an end piece for fixing and connecting hoses;

Γίμ. 5 shows in perspective a Kleniiinorrkh-Queischschl: iuchs 32 Ivzügli the end wall 24 of the

for stretching or pulling out the tube: mounting frame 22 i icls of a pump

F i g. ft and 7 are "partially" shoe parts, side anchors, connecting pieces 38. That in I ^: ig.4

View, which shows the instructions of the procedure and the connection piece 38 shown in the one

N orriehtuiu: after the [.rinding / around 1 ^: .iching of a 5 a cylindrical middle section 40 on. whose

Hose.- explain that the niLht / u a hose outer length is considerably larger than the inside

i | uetsehpunipe listen. nendurehmcsser read squeeze tube 32. To the

In the end there will be a reversal of the central abutment 40 on both sides

Method and a device according to FIG described. Fin. I zciiu a hose qui'Uch- io;: n. The hand cuts end in flat faces

pump 10, for example, the pale basic 46 and 48. Between the front surfaces 46 and 48

In a structure like the one in the USA patent, a wall serving as a through-flow opening is

3 227IW! may have described pump. The tion 50 Although the Λη-ehlußstück 38 au> one

The pump has a pressure roller assembly 12 with any suitable readily available material.

i. in a chain wheel U and an endless chain 16 am '. '-5' ial can be made ka: m. becomes a proportionate

The chain 16 is driven by the sprocket 14 in the direction of inert KunsiMoi '. for example PoKat-

ues illustrated arrow around a Ketlenführeruugskö; - Inlen

per 18 aiiüetricber .. The A.uschlul5slück 38 is used to manufacture the

On the endless chain 16, the 1 inlet end 52 of the stand together are in the same connection h several pressure rollers or pressure roller !! 20 2 ° diiickbaiLti Quetschsehi.iuchs 32 pressed until the freely dijhbar attached. Hose the middle section 40 of the connector

Like 1 i g. 3 shows, has a roughly rectangular shape closely and tightly surrounding it. This creates a very safe

Fastening sleeves 20 for the pump hose assembly, but easily detachable pump hose connection

e.g. two opposite end walls 24 and a tail piece connection. As a result of the large

26 with the fastening opening 25 of the outlet end of the squeeze tube 32 aligned with one another

intimate 28 and 30 on. "" because anchoring piece 38 is not what is left in the

Hm / squeezable: hose 32. the from ir- able to move to the right through the opening or the

"End of a common elastic and inner fabric cut-out 28 to move ... so dad on the inlet end

Sufficient strength, for example silicon- this: place is determined, as it is Fi g. ! indicates,

rubber, is made of, extends / wiped out

v.i. . openings or fasteners cuts 28 pieces 38 a similar elastic

ui: j 30 through the mounting frame 22. The shear hose 54 is attached. The hose 54 leads

cuts or openings 28 and 30 are on their to any medium that may be used after the calibration process

The bottom is semicircular so that it can be pumped through the peristaltic pump 10

Adjust 35 to the circular cross-section of the squeeze tube.

and with this one FeslsiL? form. The pump is set to the calibration point. There-

C.iiie pump or pressure plate 34 can be influenced by squeeze pump 10, the inner diameter of the Open position into the shown closed used pinch hose 32 is selected in this way. Position. In the closed sewer, that it is no smaller than the inner drizzle fits the upper part of the squeeze tube 40 scr. that of the desired or specified stream one not shown corresponds to the shape of the pinch speed. The flow hose adapted groove on the lower side of the speed or the flow depend on known-P'atte 34 a. In this way, the hose primarily fits the square of the inner pipe inner surface 36 of the plate groove and sers or cross section of the squeeze tube and the is thereby combined by the pressure rollers 20, the feed speed of the pressure rollers squeezes as shown. Peristaltic pump off.

When the peristaltic pump 10 is troubled, the pump is started for calibration. Since the sprocket 14 is driven clockwise, the sprocket 14 is driven with a constant, front d ^ ß the endless chain 16 in the direction of the indicated speed, so that the printed arrow revolves, as it is in FIGS 2 roll against the squeeze tube 32 is conical. As a result, the squeeze tube 32 will have a constant feed speed. As soon as the peristaltic pump 10 continues from the pressure rollers 20 from left to right, compressed or closed, has reached its operating state, the pump through which a liquid and / or flow contained in the hose is observed by means of a flow meter 56, or gaseous medium in the illustration after 55 If the indicated flow rate exceeds the gedcn F i g. I and 2 are pumped from left to right. Desired flow rate exceeds, as it is with the.

In the following, with reference to FIGS. 1 and 2, most of the examples described here are due to the Method and a preferred device for selecting the inside diameter of the pinch guide used of the method according to the invention is described hose 32 is the case, the inside diameter ben. 60 of the squeeze tube 32 is reduced. To this

For the purpose of setting or calibrating according to the invention, the squeeze tube is stretched in length extremely precise, predetermined flow rate. To reduce the inner diameter and in the case of a Pu.npe according to the type of FIGS. 1 and 2, the squeeze tube is thus of the flow the pump components stretched too long in the operating mode shown until the flow meter 56 confessed brought. The squeeze tube 32 is located 65 indicating the desired flow rate. Then, if between the pressure plate 34 and which it is necessary to cut off the squeeze tube 32-pressure rollers 20. th, and the outlet end by a further

Before your calibration process, the inlet end of the end piece 39 is attached to the end wall 26 of the frame

set in the same way as it explains bc blood fluid samples. With one of these

rcits with respect to the fitting 38 at the inlet endc inner diameter, a clogging of the

of the squeeze hose is described. Hoses made of solid or semi-solid materials, both

To carry out the calibration process, agglutinins, which are present in blood liquid wedge samples, can be used

Squeeze tubing 32 with any suitable 5 occurrence is avoided.

Extend the device, for example with silicone rubber for the pump hoses.

a hose clamp shown in Fig.5 60th Schuk used, which due to its high elasticity

This clamp includes two clamp arms 62 and 64, and if strength is preferred, one must have one

which at one end by means of a screw plug with an inner diameter of 0.457 mm

66. the use of aligned holes in the io as those specified by the manufacturer

Articulated arms extend, articulated to one another, tolerances are ± 0.051 mm. If you therefore

who are. "a silicone rubber tube with an inner

In arms 62 and 64, a diameter of less than 0.457 mm would be selected

pivot pin 66 matching opposite ends and if this hose happens to have a maximum to-

formed grooves or recesses 68 and 70 would have pre-15 tolerance of 0.051 mm, then would be

seen that together have a cylindrical opening such a hose is unusable because its inner

the diameter of which would be less than 0.406 mm, equal to the outside diameter. The

Knife of the squeeze tube 32 or a slightly smaller diameter of such a tube can be used

is. if the clamping arms 62 and 64 to- do not enlarge by hand.

are pressed together to the squeeze tube with ao If one for the squeeze tube 32 a

to capture the opening. The inner surfaces of the exhaust hose with an inner diameter of

Verchungen 68 and 70 can be selected with a rough 0.457 ± 0.051 mm, it is in most cases

or coarse coating, as is necessary on the part, to coat the inside diameter of this hose

len 72 and 74 is shown to the Reibungswider- after the method according to the invention in the

stood and thus the gripping effect of the clamp to pull 25 Längr until the flow rate is 25 lambda / min

improve. achieved. As mentioned earlier, the flow

The outlet end of the flow meter 56 can also be measured. Just like before-

Grasp squeeze tube 32 by hand, and if already described, then the

pull the length. Cut off the hose and place it on the connector

After cutting and attaching the 30 39 plugged in. This ends the calibration process, and

Squeeze tube 32 on the connection piece 39 is a sample flow of 25 lambda / min si-

on the other end of the connecting piece 39 is made. With a peristaltic pump with

The elastic tube 58 is attached. These multiple hoses are used to calibrate all pump

The hose serves as a connection line for the pump hoses.

outlet. 35 For a few exceptional cases in which the failure of the flow meter 56 when reaching the nominal diameter of the hose with a nominal stationary Operating condition the hose squeeze diameter of 0.457 mm is exactly 0.406 mm, pump 10 indicates the desired flow rate, then the flow meter 56 will immediately display the desired flow rate the inside diameter of the pinch flow used was 25 lambda / min. This hose already has the desired dimension. The hose can be cut immediately and put on the Ansem If the hose does not need to be plugged into the length connector 39. Since a dressing up to become. It is only cut off. The inner diameter is not necessary, and attached to the connector 39. this hose does not need to be elongated

The invention can also be used on hose too.

Apply squeeze pumps up to 16 or more 45 although the calibration method according to the invention

Have squeeze tubes. Such pumps are described for hand of a peristaltic pump,

Then one of the existing squeeze hoses, it is not besc ¹ rankt on such devices. With

corresponding number of gas or liquid to the method according to the invention and the invention

rehearse. Such pumps are, for example, in the device according to the invention, any desired ela-

U.S. Patent 3,134,263. These 50 stic hoses are calibrated. For example, in the

Pumps are used to supply analysis units- Fig. 6 and 7 a source 86 for a gaseous and

directions, as shown for example in the USA.-Pa or liquid medium, the one

tentschrift 3 241432 are described. At such an approximately constant pressure. Furthermore there are two

Systems, the pressure rollers 20, a feed end walls 82 and 84 are provided. With the shown

speed of 25.4 cm / min in relation to the 55 arrangement one can get a piece of the elastic

Have pump hoses. This allows hose 86 to be precisely calibrated in order to

set a-.n desired sample flow rate of 25 lambda / desired flow rate value. However

min, without the samples being pumped, the original inside diameter of the

clog the hoses. Hose 86 must not be smaller than the

For this desired flow rate 60 meters, which corresponds to the desired flow rate

of the liquid and / or gaseous samples The calibration process is again carried out with a

It is necessary for the pump tubing to pass through an influence meter 56. The subsequent festival

have a diameter of 0.406 i.im. If the end of the hose is positioned, it is again carried out with a

Chen inner diameter becomes a blockage of the connecting piece 39, as in the calibration of the pumping

Rent tubing through the samples. Preferred 65 hose 32.

wise, the squeeze hoses should have an inner Although in the exemplary embodiment described

have a diameter greater than 0.381 mm. len connectors 38 and 39 to set de

This will be used in connection with the pumping of the inlet and outlet sections of the hose

it can be used for the same purpose Use orrichtui.gen. So you can, for example e in the USA patent 3 353 567 use connecting or connecting sleeves, For example, silicone rubber tubing can be

glue wisely on the socket using an epoxy shark. The hose shown in Fig. 5 can also be designed differently. It is only a matter of a device you can pull the hose lengthways.

1 sheet of drawings

v ^x

Claims (2)

! .l'.cn'. claims: 1. Procedure / to adjust the by a Wedge flowing medium on a given Flow value at which a / u is large Flow the inside diameter of the pipe with constant measurement of the flow si) is reduced for a long time until the specified flow is set, thereby identifying / e i c Ii η e t. that when using an elastic Line / To reduce the flow, the line is stretched. 2. Device / for carrying out the process according to claim I, characterized. that a fastening device (24, 38; 82, 38) hold the inlet end of the resilient conduit (32; 86) stationary at the outlet end of the conduit an ivweghare clamping device (60) is clamped and that a further fastening device ac direction (26, 39; 84, 39) the outlet end of the elongated line (32.86) stationary keep.